MODELING 

LONGRUN

HOUSING DEMAND 

BY TYPE OF UNIT 

AND REGION 

Research 

Paper

FPL 308 

Forest Products Laboratory 

Forest Service 

U.S. Department of Agriculture 

1978 
1 

2 

3 

4 

5 

6 

ABSTRACT 

This report summarizes the results of research to develop an improved model of longrun housing demand for projecting future residential construction activity by type of unit and 

region. Specific submodels have been developed for household formations, type of housing 

unit occupied, and housing replacement. 

Household formations and trends in marital status are discussed. A procedure for estimating a theoretical upper limit to headship is 

described. Equations for projecting headship 

by age group are present along with a set of estimated headship rates to the year 2020. 

A detailed analysis of factors, determining 

housing choice between single-family, multifamily, and mobile home housing structures, is 

presented. Major determinates are: (1) Age of 

household head, (2) family type, (3) regional location, (4) metropolitan location, (5) household 

size, (6) income, and (7) the ratio of income to 

housing expenditures. Three types of models 

of housing choice are discussed. The are: 

(1) Individual household models, (2) aggregate 

coss-sectional models, and (3) time-series 

model. Several examples of individual housing 

models are given. 

A discussion of housing replacemednt and 

the lack of an adequate data base for statistical 

analysis is presented. A model based upon estimates of net housing replacement by age of 

structure and region is examined. 

CONTENTS Page

Introduction ..................................................................................................................... 

Household Formation Model ............................................................................................ 

Distribution of households by family type .................................................................... 

Marital status ............................................................................................................. 

Calculation of a maximum limit for headship ................................................................ 

Headship equations ................................................................................................... 

Projections of headship and households by type ......................................................... 6 

An Analysis Of Choice of Housing Types ........................................................................... 7 

Home ownership and rental housing markets .............................................................. 9 

Determinates of housing choice ......................................................................................... 9 

Housing preces, values, and rents ....................................................................................... 15 

Models of housing choice .................................................................................................... 18 

Summary of housing choice ............................................................................................... 21 

An Improved Model of Housing Replacements .......................................................................... 22 

Summary ...................................................................................................................................... 23 

(Final report on work conducted in cooperation with Oak Ridge National Laboratory, Oak Ridge, Tenn.) 

PREFACE 

Work on modeling longrun housing demand was originally begun as part of a research effort to project future timber demand 

for use in long-range planning in forestry. New 

residential construction accounts for nearly 40 

percent of wood products consumption in the 

United States. In addition repair and alternation of existing housing units accounts for over 

10 percent of all U.S. wood product consumption. Altogether about one-half of all wood 

products comsumption occurs in the residential 

construction sector of the economy. Thus, 

home building is a mojor determinate of future 

timber requirements and of the prospects of 

wood products industry. 

Substantial variations occur in the use of 

wood for different housing types in various regions of the country. It is important to disaggregate the projections of housing demand by type 

of unit and region. For example, a single-family 

house uses over 12,000 board feet of lumber in 

the Northeast while a multifamily unit uses less 

than one-half that, and a mobile houm uses 

only about a quarter as much. Houses in the 

South use only about three-fourths the amount 

of lumber as the Northeast. Long-term population shifts now favor construction in the South 

and West ands of single family houses. 

A model was previously formulated to project future residential construction activity and 

the inventory of housing unit by type of unit and 

region based upon detailed estimates of population by use and trends in the regional distribution of population. This model was adapted 

by Oak Ridge National Laboratory for use in the 

development of a comprehensive model of energy use in the residential sector of the U.S. 

economy. Partial support was provided by 

ORNL to improve the model by adding economic variables to the demographic model. 
MODELING LONGRUN 

HOUSING DEMAND 

BY TYPE OF UNIT 

AND REGION 

By 

THOMAS C. MARCIN, Economist 

Forest Products Laboratory, 1 Forest Service 

U.S. Department of Agriculture 

INTRODUCTION 

Research is described here on developing 

an improved model of long-run housing demand in the United States for projecting future 

residential construction activity as well as inventorying housing by type of unit and region 

The starting point for this research was a previously developed comprehensive demographic model of housing (Marcin, 1972). 

This model projects the longrun level of 

household and housing requirements by housing type and region based upon explicit annual 

projections of population by age group The research documented in this paper was directed 

at examining additional demographic, social, 

and economic variables to develop an improved model which includes behavioral economic relationships emphasizing measures of 

housing prices and housing cost. The main 

goals of study were to: 

(1) Develop a data base of relevant economic, demographic, social, and housing statistic variables for use in model development. 

(2) Postulate specific economic relationships based upon economic literature and theory and empirically fit econometric equations to 

1Maintained at Madison Wis., in cooperation with the University of Wisconsin 

them where data permit. 

(3) Refine and improve a working model of 

housing demand by adding economic relationships on an incremental basis beginning with a 

measure of economic activity and personal 

income. 

(4) Improve and update the model by fitting 

it to data from the period from 1950 to 1976. 

(5) Provide a completed model for projecting the number and characteristics of future 

housing demand which can be used as a component of a national timber requirements model 

and as a component of a model of residential 

energy use. 

Reformulation of the model has proven 

more time-consuming and difficult than originally anticipated in part because of time spent 

in developing the data base. The process of examining data, testing relationships, and building a model, however, has provided valuable information. Limitation of data has been recognized. New insights into the housing market 

have been developed, and directions for further research are suggested. Specifically, new 

information and insights have been developed 

on trends in household formation relative to 

marital status, the relationship of family status 

to the type of housing unit demanded, and the 

relationship of housing cost and prices to 

household income; i.e., the “affordability of 2Listed in Literature Cited at the end of this report housing.” 
A data base has been established for use 

in modelling and analysis of housing markets. 

The base consists of: (1) Computer tapes of individual housing units and household characteristics, and (2) demographic and socioeconomic data collected from various published 

reports. 

A number of specific economic relationships were formulated and examined. Attempts 

were made to establish statistical relationships 

using both time-series and cross-sectional regressing analysis. Some of the more important 

results are discussed later in the paper. 

An improved working model has been established. Headship equations which explicitly 

include personal disposable income and an estimate of maximum headship based upon 

trends in marital status and living arrangements 

for adults have been added. A model for determining the type of housing unit demand has 

been examined on an experimental basis. Estimates of housing replacement requirements 

based upon a matrix of replacements rates by 

type of unit, region, and the age of the stucture 

have also been developed on an experimental 

basis, but are not reported here. 

It is important to discuss the nature of the 

housing market at this point to better understand the appropriateness of particular socioeconomic variables relative to short- and longterm housing market response and to models 

of fluctuations in new residential construction 

versus models of the total housing stock. For a 

given set of assumptions this model generates 

an “equilibrium” level of annual residential 

construction demand. It does not, however, attempt to account for short-term changes in 

construction activity about this longrun demand level. Therefore, a number of economic 

variables, such as short-term interest rates and 

the flow of funds into savings institutions, are 

not considered in the model. 

Demographic variables become particularly important in the longrun. Trends in the age 

structure of the population, the mix of individual versus family households, the age of the 

housing stock, and geographic distribution of 

population are particularly important in longrun 

analysis. 

Housing services flow from the total housing stock of about 80 million units. New construction amounts to only about 2 to 3 percent 

of the total stock annually. Additionally, conversion of existing structures to more units can expand the number of housing units during periods of shortages. Wide fluctuations can and 

do occur from annual housing production of 

different types of housing units without greatly 

affecting the total flow of housing services. 

The development of an improved comprehensive longrun model of housing demand, 

which projects the regional distribution of 

households, housing inventory, and housing 

production by type of unit, is a complex undertaking which requires division into separate research areas. The major areas of research are 

covered in this paper. They are: (1) An improved model of household formation, (2) an 

improved model of housing choices, and (3) an 

improved model of housing replacement. In addition, we have developed specific information 

on: (a) Measures of housing cost expenditure, 

value, and price, and (b) historical trends in 

housing production by type of unit. 

HOUSEHOLD FORMATION 

MODEL 

In projecting future household formations 

in the nation, it is useful to separate movements 

caused by population changes and those 

caused by changes in the rate of household occurence for a given population age group. In 

addition, shifts in the composition of household 

types between husband-wife families, other 

families, and nonrelated individuals are also important for determining the type of housing demand. Long-term changes in marital status and 

living arrangements are important determinates of the total number and kinds of households. Economic factors such as the level of 

per capita personal disposable income are important in determining the ability of individuals 

to form separate households. Increased housing costs relative to income or a restricted 

housing supply as evidenced by low vacancy 

levels could also reduce the rate of household 

formations, in the short run. 

The effect of population change on household formation is separated from other factors 

by defining headship (Hi

) as the proportion of a 

given population (Popi

) for age group i that 

heads households (HHi

)i or 

Hi = HHi 

POPi 

2 
The total number of households is then determined by estimating the level of headship 

and the future population by age class separately. Seven age classes are used in our 

model. They are: 18 to 24, 25 to 29, 30 to 34, 35 

to 44, 45 to 54, 55 to 64, and 65 years and older. 

For statistical reasons we have combined our 

previous 15- to 19- and 20- to 24-year-old age 

groups into one category of 18 to24 years old. 

Virtually all household heads are over 18 years 

(over 99.9 pct) and this situation is likely to continue. Census population projections are available by age class for alternative fertility, mortality, and immigration assumptions and can be 

used with this model. 

Distribution of Households by 

Family Type 

The mix of household types between traditional husband-wife households, other family 

groups, and primary individuals (i.e., one or 

more unrelated persons) is an important 

factor influencing the future demand for various housing types The overall mix of household types for all age groups is summarized in 

table 1. Changes in the age-mix of the population are important in determining the overall 

mix. 

In addition to looking at the distribution of 

household types, it is also useful to examine occurrence rates, i.e., the percentage of the total 

population in each category of household. The 

occurrence rate of husband and wife households has remained relatively steady for all age 

groups for 1952 to 1976 (fig. 1). The number of 

married couples living with parents or others 

has declined substantially since 1950 and has 

offset the recent decline in marriage rates in 

younger age groups. The increased proportion 

of households headed by individuals is largely 

the result of increased headship among nonmarried individuals, previously members of 

other households. 

There has been a great increase in individual households since the early 1950's, particularly in the under-30 and over-65 age groups 

(table 2). Family groups not headed by a husband and wife have increased substantially for 

households in age groups under 45 years of 

1. The occurrence rate of husband-wife households by age group, 1952 to 1977. M 146 408 

3 
age, primarily because of recent high levels of 

divorce and resultant one-parent families with 

female heads. This is a result in part of the dissolution of marriages which occurred at extraordinarily high rates and at young ages during the 1940’s and 1950’s. The rate of occurrence of these other family groups has declined 

for households in the over-45 age group, reflecting a continued separation of intergenerational families. However, the overall proportion of other family groups has not changed 

much since 1940. 

Headship rates have now increased to the 

point where nearly all married couples (99 pct) 

live separately in households. Additional increases in headship must result from increased 

headship of the remainder of the population not 

living as couples or from dissolution of existing 

husband-wife households into two individual or 

single-parent households. Since each household has only one head a married couple automatically accounts for two people and results 

in a maximum headship of 50 percent for that 

segment of the population Cohabitation by 

nonmarried couples also results in a maximum 

headship of 50 percent for them Trends in marriage rates and the occurrence of married couples are an important factor for estimating an 

upper limit to headship Examination of historical rates of marital status is, therefore, important in determining ultimate headship rates In 

addition, the type of housing unit demand is related to the type of household occupied 

Marital Status 

Historical data on marital status show the 

percent of married women by age group remained very stable from 1890 to 1940, then increased dramatically for women under 35 in the 

2. The percentage of women married, for selected age groups under 35 years old, from 

1890 to 1976. M 146 406 

4 
For example, if all households were married 

couples, the maximum headship rate would be 

50 percent since each household has only one 

head by the Census Bureau's definition. 

A theoretic maximum for headship by age 

group is derived by examining records of marital status and living arrangements (tables 3 and 

4). Estimates of total population and population 

in households by sex and type of household for 

each age group are used to derive a theoretical 

maximum of headship: The procedure is as follows for each age group: 

(1) Add: (a) male household heads with 

wife present, and (b) wives of household heads 

to obtain the population in husband-wife 

households (note that wife of heads are 

younger on the average than their spouses). 

(2) Subtract No. 1 from the population in 

households (excluding inmates in institutions 

and armed forces overseas). 

(3) Assume 90 percent of the household 

population not in husband-wife households 

could or would want to head separate households. 

(4) Add 50 percent of No. 1 to No. 3 to determine the theoretic maximum number of 

households. 

(5) Divide No. 4 by the total population to 

obtain the theoretic maximum for headship for 

age groups over 25 years of age. 

(6) For the 18- to 24-year-old age group 

subtract children of heads not in subfamilies 

from the population basis and then proceed as 

with the other groups. 

Estimates of the future occurrence rate for 

husband-wife households by age class are 

made to establish an upper limit for future 

headship. In our present model, we simply postulate a future target level for husband-wife 

household occurrence based on the assumption that marriage rates will level off near preWorld War II levels. A possible additional decline of 10 percent in the proportion of married 

couples is assumed. We then use this as a basis 

to establish an upper limit for headship according to the procedure described previously. 

Headship Equations 

Headship rates have increased for all age 

groups since 1950. A major factor in this increase has been the steady rise in real per capita personal income in the same period. Specific behavioral relationships have been developed for each age group with real disposable 

personal income per adult 18 and over as an independent variable. 

The following functional form was used to 

estimate headship for each age class i in the 

year n: 

Hn 

i = A + B Yn-i + CHi

n-i 

where 

ai – Hi Hin = 1n( ) or the logistics transfor- Hi 

n 

n mation function 

a = an upper limit for headship 

real disposable personal 

Y = income in thousands of 1972 dollars. 

(Population 18 years and older) 

i = age class (i - 1, 2,..., 7: 18-24, 25-29, 

30-34, 35-44, 45-54, 55-64, 65 and over) 

Statistical relationships were developed using 

data for the period from 1953 to 1976. Headship 

rates were derived from household data by age 

class as of March 1 and estimates of population 

as of the data (table 5). Real personal disposable income per adult was based upon the previous year’s income since it would be more important in determining headship on March 1 

rather than the current year's income. Total National Disposable Personal Income was divided 

by the consumer price index and the population aged 18 and over to estimate Real Disposable Income per adult. The regression equations for headship and data sources are shown 

in table 6. When headship approaches the 

specified limit, within 0.01 percent, headship is 

set equal to the limit. 

Projection of Headship and 

Households by Type 

Recent high divorce rates and the decline 

in the proportion of married persons for 

younger age groups has been partially offset by 

a decline in the number of married couples living with relatives or other persons and a high 

remarriage rate among divorced persons. As a 

result, the proportion of the total population 

who live as married couples has generally not 

declined significantly by age group from 1950 

to 1976, although this proportion declined 

6 
1940s and 1950s (fig. 2). For example, the percentage of women 18 to 24 who were married 

rose from 42 percent in 1940 to 58 percent in 

1960. This level fell to 44 percent in 1976; however, this is still above the level before 1940. 

The percentage of married women in other age 

groups remains substantially above the pre1940 level despite recent declines from 

mally high marriage rates of the 1950s and 

1960s. In fact, marriage rates continued to advance for those over 55 years of age (fig. 3). 

We view the current decline in marriage 

among the younger age groups as a return to 

historical levels from the abnormally high levels 

of marriage accompanying the baby boom of 

the 1940s and 1950s. We would expect the current decline in marital status for women not to 

fall much below the historical levels of the pre1940 period, i.e., marriage levels of about 40 

percent for women 18 to 24 years old, 70 percent for women 25 to 29 years old, 80 percent 

for women 30 to 44 years old, and 75 percent 

for the 45- to 54-year-old group. Marriage levels 

for women 55 to 64 and over 65 are assumed to 

not fall below 65 and 35 percent respectively. 

and in fact are likely to remain above these levels due to better health and rising incomes 

Annual statistics indicate a trend to a high 

level of divorce However, since most divorced 

persons remarry, the aggregate effect is difficult to assess In addition, high levels of divorce 

for persons aged 25 to 54 partially reflect the 

extremely high levels of marriage in the 1950s 

and 1960s for this age group More young people may remain single in the future now that it 

has become more socially acceptable not to 

marry or have children 

Calculation of a Maximum Limit 

for Headship 

The headship rate for a given age group 

(i.e., the ratio of household heads to population) will reach a theoretical maximum based 

upon the number of husband-wife households 

and the occurrence of other household types. 

3. The percentage of women married for selected age groups over 35 years old from 1890 

to 1976. M 146 407 

5 
since 1970 for persons under 35, back to the 

levels of the mid-1950's. In modeling household 

types we estimate the occurrence of husbandwife household and other family households by 

age class Households headed by individuals 

are then derived from projections of total headship from our regression equations Projections of household types are used to estimate 

the distribution of housing types 

Available evidence indicates that the family 

type is probably the most important factor in 

determining housing choice Most families 

(over 75 pct) live in single-family housing regardless of income while slightly over half of all 

individuals live in multifamily structures Future 

research efforts will be directed at developing 

a model of household formation by family type 

An important improvement in modeling 

headship is the development of a model to simultaneously determine the occurrence of 

husband-wife and other household types by 

age class We can then take advantage of the 

fact that headship is by definition limited to 50 

percent for couples to derive a realistic upper 

limit to headship. In addition, a submodel of 

marital status is also important for determining 

both the upper limit of headship and the number of husband-wife households The models 

of marital status and household occurrence by 

family type could then be related to social and 

economic variables wherever possible to project households by type 

Headship rates were projected to the year 

2020 using the equation in table 6 for growth 

rates of 1 and 2 percent annual growth in real 

per capita disposable income per adult (table 

7). 

Headship rates increase in all age groups 

as income increases The age groups for 

household heads over 35 years old begin to approach their theoretic upper limits in the 1990’s 

and alternative assumptions about income 

have less and less of an effect For example, 

headship rates vary from 67.0 to 67.5 percent 

for the 65 and older age group in the year 2000 

and 67.7 to 68.0 percent in the year 2020 for the 

two assumptions about income growth 

Headship rates vary more widely for the 18­

24 and 25-29 age groups in response to alternative assumptions about income growth because they are farther from upper limits 

For example headship rates for the 18-24 

group vary from 23.9 to 25.7 percent in the year 

2000 and 25.6 to 28.9 percent in 2020. These 

headship rates, combined with the Census Bureau's Series ll population projections, produce household formation projections which 

compare fairly closely to Census Bureau's middle and lower projections for households 

AN ANALYSIS OF CHOICE OF 

HOUSING TYPES 

Yearly shifts in new housing production by 

type of unit can lead to misinterpretations of 

what is happening to total housing supply; new 

housing provides only a small fraction of the 

overall supply of housing services to consumers. Changing economic and demographic 

factors lead to cycles in housing production for 

different types of units over time (Campbell, 

1966). For example, major apartment booms 

occurred in the 1920’s and from 1960 to 1973. 

Overall, since 1900 approximately 70 percent of 

all housing construction has been single-family 

housing units (including attached units) and 30 

percent multiunit. The analysis of housing 

choice is further complicated by the conversion 

of existing single-family housing units to multifamily units and the emergence of the mobile 

home. In the the mobile home became 

an alternative supply of housing which provides service in the form of chattel rather than 

real estate. Many attributes of a mobile home 

are similar to single-family houses, and they 

may be considered as another form of singlefamily housing. (The Census Bureau now reports a combined figure for single-family structures and mobile homes.) 

New regulations have brought the mobile 

home more and more under the control of the 

institutional forces in the conventional housing 

market. As such the mobile home is evolving 

into another form of industrialized housing. In 

doing so it is losing many of the attributes of a 

low-priced form of housing exempt from typical 

community building codes and real estate 

taxes. 

Basic data on the housing inventory by 

type of unit are available beginning with the 

1940 Decennial Census of Housing. In addition 

to the 1950, 1960, and 1970 Housing Censuses, 

data are also available from the Annual Housing Surveys begun in 1973. As an overview of 

housing, we have summarized the distribution 

7 
of housing types for 1940 to 1976 (table 8). 

Historically, the market share of annual 

housing production has widely between 

single-family and multifamily housing units. The 

market share of multifamily units ranged between 20 and 45 percent of nonfarm housing 

starts from 1900 to 1930. From the early 1930's 

to 1960, the multiunit market share was abnormally low-between10 and 20 percent of housing starts-relativeto the 30 percent share multiunits had of the total housing inventory in 

1940 and 1950 (fig. 4). Conversion of large, single-family houses to apartments, rent controls, 

the fear of rent control, and the highly successful housing mortgage guarantee programs of 

the Federal Housing Administration and Veterans Administration contributed to the large 

market share single-family homes had of the total housing market. 

The market share in multiunits increased 

dramatically in the 1960’s, rising from 19.5 percent of housing starts in 1959 to almost 46 percent in 1969. It remained at nearly 45 percent 

for the period from 1970 to 1973 and then fell to 

about 24 percent for 1975 and 1976. This increase in apartment construction is less dramatic when mobile home shipments are also included in the housing production base. Including mobile homes, the market share of multiunit 

structures increased from 18 percent in 1959 to 

peaks of about 36 percent in 1969, 1971, and 

1972. It then fell to about 20 percent in 1975 before rebounding slightly to 21 percent in 1976. 

The apartment boom of the 1960’s and 

early 1970’s can be largely explained by (1) the 

age of the apartments stock in 1960 (few new 

structures of five or more units had been produced since the 1920’s), (2) an excess supply 

of single-family houses, (3) a return of housing 

production to its long-term share of the total 

housing inventory of about 28 percent, and (4) 

demographic factors such as the increase in 

one-person households and the large increase 

in the number of young households under 30. 

The market share of mobile homes as a 

percentage of housing starts plus reported mobile home shipments has increased from about 

7 percent in the late 1950's to almost 22 percent 

in 1969. After staying at a plateau of about 20 

percent for the period 1970 to 1974, their market share dropped to 15 percent in 1975, 14 

percent in 1976, and 12 percent in 1977. This 

decline resulted in part from overbuilding and 

repossession of mobile homes, which caused 

lenders to be much more conservative in extending credit. 

The mobile homes share of the year-round 

occupied housing market has increased from 

0.7 percent in 1950 to 1.3 percent in 1960 and 

3.1 percent in 1970 to 4.6 percent of the housing stock in 1975. 

A substantial share of reported mobile 

home shipments fail to show up in subsequent 

counts of mobile homes occupied as primary 

households (table 9). 

A number of explanations for this apparent 

4. New housing starts by type of unit from 1900 to 1977, with mobile home shipments from 1947 

to 1977. M 146 409 

8 
discrepancy are possible First vacant units 

and second homes are not included in the census or survey counts This is particularly important in the 1972 to 1973 period when the mobile 

home boom may have led to excessive inventory buildup by dealers. Second, placing mobile 

homes on permanent foundations or the attachment of a porch or room may have led to 

some counting of mobile homes as single-family houses. Third, there may have been some 

overreporting of shipment data On a 

basis we count 75 percent of reported mobile 

home shipments as a satisfying primary yearround housing demand 

The mobile home has changed significantly over the last 20 years. For example, the 

first 10-foot-wide models were introduced in 

1955; 12-foot-wide models came into mass production in 1962; and 14-foot-wide models were 

introduced in 1969. Now expandable models, 

double wide models, and even triple-wide 

models similar to single-family houses are available The adoption of a nationwide mobile 

home standard code by the Department of 

Housing and Urban Development (HUD) in 

1976 is a major milestone in the evolution of 

mobile homes to another form of manufactured 

housing. This code dictates 2 by 4 framing, insulation, and fire spread standards similar to 

conventional construction 

This code, together with government programs to allow long-term mortgage financing 

on certain types of mobile homes, indicates 

that the mobile home is now coming under the 

control of the institutions and regulations of the 

conventional housing market As such the mobile home is losing many of the special advantages of being outside the control of the conventional real estate system (Drury 1973). As a 

sign of the times the Mobile Home Manufacturer's Association has recently changed its 

name to the Manufactured Housing Institute 

Home Ownership and 

Rental Housing Markets 

In examining historical trends in the typemix of the housing stock, it is important to look 

at tenure of home ownership versus rental markets The home ownership market is generally 

demand-determined since consumers make a 

decision to buy or build a house of their choice 

Income and assets generally determine the size and value of the housing unit. On 

the other hand the rental market is generally 

supply-determined, i.e., the renter accepts 

what is available on the market and the investors will only supply units which will produce an 

acceptable rate of return on investment after 

construction costs, mortgage interest, and operating costs are taken into account. In this 

case, it is generally more economical to produce muItiunit structures. 

From 1940 to 1960 ownership increased 

sharply, rising from 43.6 to 62 percent. Since 

1960 ownership has continued to increase 

slowly, reaching 64.8 percent in 1976. Singlefamily homes have steadfastly maintained the 

lion share of the ownership market for the last 

40 years. The market share of single-family 

housing in the home ownership market has remained surprisingly constant from 1940 to 

1976, varying between 87 and 89 percent of the 

total owner-occupied housing stock (table 10) 

Despite extravagant claims of large shifts to 

condominium apartment ownership, the market share of multifamily units in the ownership 

market has declined from nearly 11 percent in 

1950 and 1960 to less than 6 percent in 1976 

Mobile homes share of the ownership market 

has risen from about 1 percent in 1950 to over 

6 percent in 1976 

Trends in the type mix of the rental housing 

market are quite different. Single-family housing units have declined from 57 to 32.5 percent 

of the rental housing market from 1940 to 1976 

As further evidence of the overbuilding of single-family houses in the 1950’s, we note that 

the single-family unit share of the rental market 

increased from 44.7 percent in 1950 to 48.2 

percent in 1960 despite the long-term decline in 

rental of single-family homes (Rental of multiunit structures is generally more economical 

because operating and maintenance costs can 

be spread over a number of units ) 

Multiunit structures have correspondingly 

increased their share of the rental housing market except for the 1950’s when the oversupply 

of single-family houses temporarily filled much 

of the rental demand. Mobile homes are a 

factor in the rental market with a 2.5 percent 

share of the rental housing market in 1976. 

Determinates of Housing Choice 

A number of cross tabulations have been 

prepared which relate the type of housing consumers live in to major household characteris9 
tics such as age of head, family type, tenure, income, region of the country, and metropolitan 

location. At this point, it is useful to examine 

housing occupancy relative to these characteristics for 1960, 1970, 1973, 1974, and 1975. The 

cross tabulations were based on 1-in-1,000 

public use sample tapes from the 1960 and 

1970 censuses and the total survey sample of 

the 1973, 1974, and 1975 housing survey. Each 

sample contains over 50,000 households. Age 

of household head is with each of the other major determinates in the following section since 

it is a primary determinate of housing choice. 

Age of Household Head 

The most important factor in determining 

the type of housing people choose to live in is 

the age of the household head. By age 30, most 

household heads live in single-family housing. 

From ages 35 to 65, nearly over 75 percent of 

all household heads live in single-family houses 

(fig. 5). What’s more, this relationship has remained virtually constant from 1960 to 1975 despite wide variations in the mix of housing production between houses, apartments, and mobile homes during this period. Household 

heads over 65 show a strong preference for single-family houses with over 70 percent living in 

houses. Even households headed by primary 

individuals (one or more unrelated persons) 

show a strong age relationship with the majority 

of middle-age people, where most have determined where they will live, their career, and 

have married. They prefer the permanence and 

privacy of a single-family house. In addition, 

many houses, particularly in rural areas, are 

simply passed from one generation to the next 

without ever being sold. From a consumptionsaving viewpoint, middle age is the time of capital accumulation for the consumer. Investment 

in a house provides an excellent way to build 

equity since home ownership is the only practical tax-sheltered investment available to most 

people. Home ownership is now viewed as an 

investment by most people and as a protection 

against inflation. Thus rising housing prices encourage the preference for single-family home 

ownership rather than discourage it as conventional economic logic might imply. 

As a measure of the effect of age alone on 

single-family house choice, we have calculated 

regression coefficients for housing type occupancy based upon the 1973 and 1974 housing 

surveys. Multifamily house occupancy was 

found to decrease for all age groups when the 

effects of family status, income. household 

size, and location were accounted for (tables 

11 and 12). Regression analysis for 1960, 1970, 

and 1975 produced similar results. A study by 

Carliner (1 974) on home ownership based upon 

the 1967 Survey of Economic Opportunity also 

confirms the age relationship of greater single 

family housing occupancy with increased age. 

Household Type 

Household type is also an important factor 

in determining housing choice. The overwhelming majority of husband-wife households 

live in single-family houses-overall nearly 80 

percent with about 86 percent for household 

heads 35 to 54 years of age. From 1960 to 1975 

there was actually a slight increase in the percentage of married couples over 30 living in single-family houses despite the decline in singlefamily housing production (fig. 5). Multiunit occupancy on the other hand declined substantially for couples between 30 and 65 years of 

age and remained about the same for those 

over 65. Mobile home occupancy increased 

steadily from 1 to about 3 percent for couples 

in all age groups with a relatively higher proportion in younger and older groups. 

A category called other families largely 

consists of single-parent households. Female 

heads are by far the most common. In 1975 

about 60 percent of this category lived in single-family homes, 36 percent in multifamily 

structures, and 4 percent in mobile homes. Single-family occupancy increases with age with 

over 70 percent of those 45 years and older living in single-family houses. Furthermore, this 

pattern has remained unchanged from 1960 to 

1975. 

The third and most rapidly increasing category of household is the primary individual. 

This group (one-person households and nonrelated individuals living together) is most likely 

to live in multiunit structures. However, the predominance of apartment living is not as high as 

one might expect. For 1970 and 1975, about 50 

percent of primary individuals lived in multifamily housing units, about 46 percent lived in single-family houses, and 4 percent in mobile 

homes. Housing occupancy is age-related for 

10 
5. Housing occupancy rates by type of unit and family type for 1960, 1970, and 1975. M 146 412 
this group. For example, nearly 75 percent of 

individuals under 30 years of age live in multiunit structures while about 55 percent of 

those over 55 years of age live in single-family 

houses. 

We may summarize our results of housing 

type occupancy as follows: 

(1 ) Single-family housing remains the dominate housing type for husband-wife households, and in fact, has slightly increased its 

share of the market for households in the over30 age group since 1960. About 86 percent of 

all husband-wife households aged 35 to 54 

lived in single-family houses in 1974 and 1975. 

(2) Multiunit occupancy has only increased 

for younger couples who are renters. There is 

little evidence that older couples are moving to 

apartments or mobile homes in large 

numbers-nearly80 percent of couples over 65 

live in single-family homes. 

(3) Single-family housing is the predominate type of housing for other families in over30 age groups and primary individuals in over55 age groups, and there has been little change 

in these housing preferences since 1960. 

(4) Mobile home occupancy has increased 

for all age groups from 1960 to however, 

it is primarily the under-30 group who live in mobile homes. Primary individuals have a slightly 

higher occupancy rate for mobile homes regardless of age. Householders over 65 occupy 

only about an average proportion of mobile 

homes despite claims that large numbers of 

them are moving to this type of housing 

(5) There has been remarkably little 

change in patterns of housing choice from 

1960 to 1975 for household heads over 30 

years of age, when age and family type are considered, despite wide swings in housing production by type of unit. 

The mix of household types has changed 

significantly since 1950. The proportion of 

households headed by single persons and nonrelated individuals has increased from 11 percent to over 23.8 percent from 1950 to 1977. 

Correspondingly the percentage of traditional 

husband and wife households has fallen from 

78 to 64 percent in the same period. Other families now account for 12 percent of all households, up from 11 percent in 1950 but still below 

the 14 percent level for this category in 1940. 

Tenure 

An important distinction exists between 

housing types in the ownership and rental markets. Home ownership is almost synonymous 

with single-family housing (table 13) This relationship has remained the same for 1960, 1970. 

and 1975 even though home ownership rates 

have been increasing Mobile homes have increased their share of the ownership market 

particularly for households in under-30 age 

groups However mobile home ownership was 

still less than 5 percent in 1960 for those age 

groups over 35 including the elderly. The failure 

of the 65 and older age groups to show a larger 

than average share of mobile home ownership 

may be because older mobile home buyers retain the old homestead and acquire a mobile 

home as a second home which is then excluded from census data. Multifamily units have 

declined as a share of the ownership market 

since 1960 despite the recently condominium housing boom. Even among the elderly, multiunit share of the home ownership 

market was only 10 percent in 1975, about the 

same as it was in 1960. It may be that growth in 

condominium ownership in large apartment 

buildings is being more than offset by a decline 

in ownership of older smaller structures–duplex, converted houses with apartments etc.– 

particularly in central cities. 

Overall home ownership rates have significantly increased for all households 25 to 64 

years of age from 1960 to 1975 and remained 

about the same for those under 25 and over 64 

What's more, the proportion of all households 

who own single-family houses also increased 

for the middle-age groups since 1960 (table 

14). 

Over two-thirds of all households and 

about 80 percent of husband-wife families in 

the 35- to 64-year-old range owned single-famhousing in 1975. Preliminary data indicate 

that these rates have increased slightly since 

then This is in sharp contrast to the widely publicized view that people are being priced out of 

the single-family housing market. In fact, since 

1950 we have had a number of housing programs to increase home ownership. In addition 

to the FHA and VA mortgage guarantee programs we have recently had the HUD Section 

235 housing program to assist moderate-income people to buy houses. Special consider12 
ation has also been given minority groups to aid 

them in buying houses. Women are now being 

given equal consideration with men in qualifiation for home mortgages both as single persons and as joint income earners with their 

spouses Those developments increase the potential market for single-family homes. 

Multiunit housing’s share of the rental market has increased substantially since 1960-rising from 51 to 65 percent in 1975. This increase 

has occurred in all age classes. However, multiunit housing rental occupancy has not increased as a percentage of all households in 

those households aged 35 to 64 (table 15). 

Thus, the increase in rental of multifamily units 

has been IargeIy concentrated in househoIds 

under 30 and to a lesser extent in households 

over 64. Middle-age persons who rent are still 

more likely to rent a house (table 1). 

Rental of single-family houses has fallen 

sharply since 1960. This reflects in part the increase in ownership by families i.e., former 

renters who bought houses Most new construction for the rental market IS multiunit structures, because it is more economical to spread 

Iand, construction and operating cost across 

multiple units. High interest rates and construction costs make even multiunit construction unprofitable in many areas without government 

subsidizing or increases in rents of 20 percent 

or more from 1975 levels. 

As a Chicago real estate executive, Lawrence H. Cleland, views the rental market 

(Professional Bldg., Jan. 1977): 

Unless there is a turnabout in the cost 

of building and operating rental 

ments or changes in government housing 

programs the next generation of renters 

will face these facts 

Few apartments 

(2) Smaller apartments 

(3) Smaller apartment complexes 

(4) Paying all their utility bills 

(5) A return to basic shelter with few 

or no amenities 

(6) Greater emphasis on 

refurbishing 

In addition to high interest rates, construction cost land costs and rising utility 

ment construction is becoming increasingIy 

more complicated and costly in urban areas because of maintenance and tax rates, new land 

use restrictions, and safety standards 

ment investment is also discouraged by new tax 

laws amortizing cost over longer time periods 

and the threat of rent controls 

Region 

The housing type-mix also varies widely by 

region of the country, location in or outside of 

metropolitan areas, and size of metropolitan 

areas Single-family housing and mobile homes 

have a substantially smaller share of the housing market in the Northeast, and multiunit structures have a correspondingly larger share. 

About 42.6 percent of the housing inventory in 

the Northeast was multiunit structures in 1975 

as compared with 27.8 percent for the entire 

United States The South has the highest proportion of single-family houses and mobile 

homes and the lowest level of apartments The 

North Central region has a slightly higher than 

average proportion of single-family houses 

while the West has a higher than average share 

of mobile homes These regional variations 

have remained fairly constant since 1940, although there has been a moderate increase in 

the relative share of apartments in the South 

and West since 1960 because of the rapid 

growth of cities in these regions (table 16) 

Metropolitan Versus Nonmetropolitan 

Areas 

Major differences also exist in the distribution of housing types inside and outside of 

standard metropolitan statistical areas (SMSA). 

Within SMSA’s there also exist substantial differences between the housing stock inside the 

central cities and that of "suburban" areas. 

While suburban consists primarily of suburbs, 

outside the central cities, it also includes rural 

areas beyond suburbs in ?he designated metropolitan area counties. As one might, guess, 

nonmetropolitan areas have a substantially 

higher percentage of single-family houses (79 

pct in 1974) and mobile homes (9 pct in 1974) 

than metropolitan areas. Central cities in metropolitan areas have almost no mobile homes 

and nearly half of their housing units are multifamily. Suburban areas have slightly more single-family housing (72 pct in 1974) than the U.S. 

share (68 pct in 1974). 

13 
6. Housing type occupied relative to income and family type for 1975. M 146 410 M 146 411 

14 
Income 

Income is an important variable in determining the type of housing people choose to 

live in. A wider range of housing choices will 

presumably be available to persons of higher 

income. In addition, the tax advantages of 

home ownership are an incentive for higher income households to own homes. And, if lower 

income people are being priced out of the single-family housing market, then a strong relationship should exist between type of housing 

occupied and income. 

In general, as income increases more 

households live in single-family houses (fig. 6). 

However, over 56 percent of all households 

making less than $5,000 in 1975 still lived in single-family housing. What’s more, about 72 percent of all husband-wife households making 

less than $5,000 in 1975 lived in single-family 

housing. Housing type occupancy is only moderately related to income when households are 

separated by family type. Most families, husband-wife, and others live in single-family 

houses, while the majority of primary individuals live in multifamily housing. In fact, a higher 

proportion of lower income individuals (mostly 

older persons and people living in rural areas) 

live in houses than higher income persons. Mobile home occupancy is highest among households with incomes under $10,000 in 1975­

about 6 percent of all households. Multifamily 

housing occupancy is negatively related to income. However, the income relationship appears to be less important than the influence of 

age and family type on housing choice. 

Income itself varies significantly with age 

of household head and family type. Income is 

highest for household heads 35 to 54 years of 

age. For example, in 1975 these families averaged $19,000 in income as compared to an 

overall average for families of $14,000. Unrelated individuals had income much lower than 

families. 

Housing Prices, Values, and Rents 

Trends in prices of houses, mobile homes, 

and rents are important factors in determining 

housing choice The exact relationship between the price for different housing types and 

housing type occupancy by households is 

complex as most housing services come from 

the existing housing inventory which also 

serves as the average family’s primary equity 

investment. Prices of new housing units represent only a small fraction (about 2-3 pct) of flow 

of housing served from the total housing 

inventory. 

Conclusions based upon price-series for 

new housing units about overall housing occupancy are misleading. Prices of houses are 

largely determined by the availability and cost 

of financing, consumer’s incomes and assets, 

and the supply of available houses. Rapidly rising prices indicate a strong demand and owners of existing houses profit. Conversely, an oversupply of apartments in many areas after the 

housing boom of the early held rents 

down to an unprofitable level for investors because of lack of demand. Change in the size 

and quality of new house units are usually not 

included in new housing price indices. 

We have constructed an index of average 

new house prices from 1947 to 1976 based 

upon the average sales price of new housing 

units as reported by the Census Bureau for 

1963 to 1976 and an index of average house 

construction cost reported from 1947 until 

1971 (U.S. Bureau of Census, 1977; Davidson, 

1973). The index of construction cost included 

only labor and material cost. Our composite index was developed by adding on an allowance 

of 25 percent for other costs prior to 1963 to the 

construction cost index. This index shows a 

very close relationship to an index of family income from 1947 to 1976, except when it was 

distorted for 1969 to 1973 by housing subsidy 

programs to provide new housing for low and 

moderate income people. The index of average 

housing cost caught up to the family income index after 1973 (figure 7). Thus, in the long run, 

family income is a major determinate of housing 

prices (Atkinson, 1966). 

Housing is one of the few items which demonstratively establishes social class in America. 

Consumers generally bid up the price of existing houses in prestigious areas or build expensive large new houses to establish social status. Housing programs which liberalize financial terms or indiscriminately provide more 

money for housing will increase the nominal 

price of houses without necessarily increasing 

the supply of housing service. Programs of 

housing allowance and subsidies without increase in supply will only raise nominal housing 

cost and shift housing services in favor of those 

15 
7. The relationship of average new housing price, and home ownership cost to family income, 1947 to 

1976. 

receiving subsidies from the next income class 

above them. 

Another indicator of housing price is property value for single-family houses on less than 

10 acres reported in the Decennial Housing 

Censuses and The Annual Housing Surveys. 

Median property value has increased from 

$7,400 in 1950 to $29,500 in 1975-anincrease 

of 392 percent. This compares to an increase of 

the average new house price from $10,844 in 

1950 to $42,900 in 1974-anincrease of 396 

percent. The median price of new houses was 

$39,300 in 1975. Thus, we see that average values or prices of all housing are considerably 

below new housing prices and that people most 

often buy or exchange used houses. 

Housing price indices for multifamily 

houses and mobile homes are not readily available. An index of rents may serve as a proxy for 

multifamily housing costs. Two sources of rent 

information are available: The rent component 

of the consumer price index (CPI) (U.S. Bureau 

of Labor Statistics, 1977) and rents paid as reM 146 413 

ported in the Decennial Census of Housing and 

The Annual Housing Surveys. The CPI rent index does not fully represent changes in rents 

since it is based on a standard, moderately 

priced city apartment (Grebler and Maisel, 

1963). The median rent as reported in the Census has increased roughly twice as fast as the 

rent index since 1940. For example, the median 

census rent increased 363 percent from 1950 

to 1975 while the CPI rent index rose by only 

206 percent. The median census rent also corresponds more closely to a Boeckh index of 

changes in residential construction costs 

(compiled by the American Appraisal Co., Inc. 

for typical construction costs in 20 cities) (Construction Review, 1977). Information on mobile 

home values is available beginning with the 

1974 Annual Housing Survey (it was not included in the 1973 survey). 

An average price for new mobile homes 

was estimated based upon industry data for total value and number of shipments. Prices for 

average mobile homes were constant in the 

16 
8. The relationship of average mobile home prices to average new housing prices, 1947 to 1976. 

1950’s and 1960’s and they became less expensive relative to new single-family houses. In 

the 1970’s, increased size and quality standards for mobile homes led to doubling of their 

average price-anincrease even greater than 

average new single-family housing prices (fig 

8). 

Another measure of the relative cost of single-family housing is the consumer price index 

of home ownership cost which started in 1953. 

This index is a composite of many factors such 

as new house prices taxes, first-mortgage interest utilities, fuel and maintenance costs 

(U.S. Bureau of Labor Statistics, 1977) As such 

it should measure the relative cost of home 

ownership for the existing housing stock When 

this index is plotted against an index for median 

family income and all consumer prices, it indicates home ownership was relatively more expensive in the 1950’s; home ownership then became cheaper relative to family income until 

1967 (our base year) and has remained relatively the same since What this suggests is that 

M 146 414 

home ownership was relatively cheap as compared to income for the years from 1967 to 

1972. Home ownership costs have increased 

more rapidly than income since 1973, and in 

1976 the ratio was about the same as it was in 

1967. 

Other measures of the relative cost of 

housing are ratios of housing value to income, 

rent to income, and housing expenditures to income. In 1960, value-to-income ratio for singlefamily houses was about 2. By 1970 the overall 

ratio fell to 1.8–an unusually low level and further evidence of the historical cheapness of 

single-family housing then. In 1975, the median 

house value was again about two times the income of its occupant 

Median gross rent as a percentage of current income also fluctuates in a narrow range 

Rent expenditures have increased from about 

20 percent of income in 1960 to about 23 percent for 1973 to 1975. One might guess that single-family homeowners spend more of their income on housing than renters. However, re17 
cent data on housing expenditures indicate 

that this is not true. Median expenditures by 

homeowners for taxes, fuel, utilities, water, 

mortgage payments, garbage collection, and 

property insurance was only 18 percent of income for single-family properties with mortgages and only 11 percent of income tor those 

without mortgages according to data from the 

1975 Annual Housing Survey. Thus, on the average, homeowners were only spending 16 percent of their income on housing (not including 

the imputed rent for their equity investment) 

while renters spent 23 percent of their income 

on housing. Mobile home occupants who were 

owners spent about the same percentage of 

their income on housing as single-family 

homeowners. 

These data on expenditures indicate that 

once a household obtains a single-family house 

or mobile home, overall expenditures are on the 

average lower than the renter; in general, people are not being priced out of the housing market but could actually increase their expenditures on housing. 

Models of Housing Choice 

Three general types of models are possible 

for the analysis of the type of housing units 

consumers choose. They are: (1) Individual 

household cross-section regression models 

which match housing choice to characteristics 

of individual households and housing units, 

(2) aggregate cross-section regression models 

comparing differences in housing types among 

states, SMSA’s or other geographic subdivisions, and (3) time-series models of the market 

share of house production for different housing 

types. 

The individual household record model approach is best suited to the data from the annual housing surveys. For the first time, general 

data on housing expenditures are available 

from the 1974, 1975, and 1976 annual housing 

surveys. (This was not included in the 1973 survey.) These models provide predictive equations for determining housing choice by age 

groups directly from survey data. 

Time-series models of housing production 

are easy to construct because of the availability 

of data on housing production by-type of unit 

and of numerous time series of economic variables. But new housing production provides 

only about 2 to 3 percent of the total housing 

flow of housing services in any year Wide 

swings may occur in the marginal additions to 

the housing stock without changing the overall 

distribution of housing types very much. This 

approach might be used to develop a relationship for the mobile home share of the housing 

market as rates of occupancy of this type have 

changed greatly from year to year because of 

wide swings in mobile home production. 

Aggregate cross-section regress ion 

models are a second approach to estimating 

housing market share. This approach has the 

advantage of providing price elasticities between different housing types if adequate data 

are available. Until recently, however, no data 

were available on housing expenditures except 

for rental properties. Data are available on 

property value for single-family, owner-occupied housing units on less than 10 acres. 

Individual Household Record Models 

These models are useful for examining a 

large number of factors related to the type of 

housing people live in. The dependent variable 

used in these models was a dummy or dichotomous variable for the probability of a household occupying a particular housing type. The 

following independent variables were used: 

Region of the country 

Age of household head 

Family type 

Location inside/outside SMSA 

Household size 

Household income 

Housing income ratio

Dummy variables were used for region, age 

of household head, family type, and location in 

SMSA. Results of this analysis have been used 

on an experimental basis to estimate changes 

in housing occupancy from 1960 to 2000. This 

analysis indicates that the market share of single-family housing is negatively affected by current trends toward more individual households, 

declining household size, and rising housing 

expenditures as a percentage of income. However, these trends are offset by migration 

trends away from the Northeast and away from 

central cities, increased real income, and after 

1980, a shift in the age distribution of households away from young households. 

These types of models require substantial 

amounts of information. We must project all independent variables. A model for estimating 

18 
multifamily unit occupancy based on 1973 

regression equations and estimated changes in 

housing occupancy by type of unit in 1990 are 

shown in table 11. This particular model does 

not the housing expenditure to income 

ratio, since housing cost data were not available in 1973. 

As a measure of the usefulness of this approach, the estimates indicated in table 17 are 

made for the percent of multifamily housing 

from 1960 to 2000. 

A second individual household model is a 

variable for housing expenditures relative to income. Separate equations were developed for 

single-family, multifamily, and mobile home 

units with dichotomous dependent variables 

for the probability of a household occupying a 

particular housing type. A variable to measure 

the relative cost of housing was added to the 

independent variables listed in the previous 

model. Total housing expenditures (incIuding 

mortgage payments, taxes, insurance, utilities, 

fuel, and trash pickup) by consumers was used 

as the variable for housing cost A rent value 

was not inputed to homeowners equity because we feel that most owners view their equity as a tax shelter investment (generally a very 

profitable one) and not a liability Gross rent (including utilities, fuel trash pickup and parking) 

was used as the measure of expenditures for 

renter-occupied units Single-family units on 

more than 10 acres, owner-occupied multifamily units and rental units without cash rent were 

excluded because no data were collected for 

them Total expenditures, including site rental, 

were used for owner-occupied mobile homes 

and gross rent was used for rented mobile 

homes The expenditure-to-income ratio was 

used for rented mobile homes. The expenditure-to-income ratio was used for each household as a measure of relative expense of housing An example of this type of model is presented in table 12. 

The following variables were used in the analysis 

Dependent variables 

Dummy variable for living in multiunit 

Dummy variable for living in mobile home 

Dummy variable for living in one-unit house 

independent variables 

Number of persons in household 

Dummy variable for living in Northeast 

Dummy variable for living in North Central 

Dummy variable for living in West 

Dummy variable for central cities of 50 largest SMSA’s 

Dummy variable tor outside SMSA s 

Dummy variable for age group 25 to 29 

Dummy variable for age group 30 to 34 

Dummy variable for age group 35 to 44 

Dummy variable for age group 45 to 54 

Dummy variable for age group 55 to 64 

Dummy variable for age group 65 and over 

Dummy variable for families other than husband-wife 

Dummy variable for individual households 

Household income previous year 

Ratio of housing expenditures to income 

The following variables were omitted as reference variables for use with other dummy variables 

Region-South 

Age group–18 to 24 years old 

Family type-husband-wife households 

SMSA location-suburbsof large SMSA s and small SMSA s 

19 
The regression models use weighted observations of 1975 data. Each observation was 

weighted based upon the sample design of the 

survey. 

All variables appear significant. However, living 

in the Northeast, in large cities, being a household head over 45 years of age, and heading an 

individual household are particularly 

significant. 

Another individual household record model 

was estimated using separate equations for 

each age of the seven age groups and three 

housing types. The results of this analysis using 

1976 data are summarized in tables 18 to 21. 

One result of this analysis is the relationship of 

income and the expenditure-to-income ratio for 

various age classes for single-family housing 

occupancy. For age groups under 45 expenditure-to-income ratio coefficient was positive for 

single-family homeowners and negative thereafter. This suggests that single-family homeownership is viewed as an equity investment by 

younger households and that consumers use 

housing as a means to build capital, as might 

be expected from a Consumer's life-cycle of 

capital saving in middle age for retirement. In 

addition, income has a strong positive relationship to single-family housing occupancy for the 

younger households. The relationship progressively weakens until it actually becomes negative for the group over 65. This again illustrates 

that homeownership is an equity investment 

with tax shelter advantages which is used to 

build capital during the consumer’s capitalbuilding years. In later years, these relationships dissipate as capital diminishes. 

Aggregate Cross-Sectional Regression 

Model 

Two aggregate cross-section models have 

been constructed. One uses state data from the 

1970 Census. The second uses data from 125 

standard metropolitan statistical areas obtained from the 1975 Annual Housing Survey. 

Both models are preliminary. This approach, 

however, provides some information of interest 

on the elasticities of demand of various housing types. 

in the state model housing cost variables 

were: (1) Median value of single-family houses, 

(2) median rent value, and (3) an average mobile home value derived from depreciated values of the existing mobile home stock in 1970. 

The mobile home cost variable is not adequate 

because it is not based upon actual market 

value of mobile homes and does not account 

for other costs such as site, rent, or property 

value if the site was owned. Median rent is a 

proxy for multiunit cost; however, about onethird of all rentals are single-family units. The 

dependent variables were the proportion of 

three housing types in the housing stock of the 

States. Independent variables used were: 

Median house value, 

Median rent, 

Average depreciated mobile home value, 

Proportion of population in 

central cities of SMSA’s, 

Proportion of population in SMSA’s 

outside central cities, 

Proportion of husband-wife families, 

Proportion of nonhusband-wife families, and 

Average personal income. 

A logistic transformation was used with 

each market share to assure that each market 

share has been 0 and 1 for any set of independent variables (Lin, Hirst, and Cohn, 1976). Other 

model formulations were tried; however, the 

one present here is an illustration of the results 

(table 22). 

The SMSA cross-sectional regression 

model is based upon expenditure data for single-family houses, multifamily units, and mobile 

homes. For rental units of all types, gross rent 

is used as the measure of expenditure. For 

owner-occupied single-famiIy units and mobiIe 

homes, reported housing cost was used as the 

measure of expenditure. Cost data were not 

collected for owned multifamily units and units 

on properties of more than 10 acres, so these 

units were excluded from the analysis. Expenditure data were summarized by SMSA from the 

1975 Annual Housing Survey data tape (data 

were also summarized for 1974). The proportion of occupied housing types and the level of 

household income was also summarized for 

each SMSA. Mobile homes were poorly represented in many SMSA’s since they are only a 

small share of the total housing market and are 

generally concentrated in rural areas. The ratios of housing expenditures to income by 

housing type were used as independent variables in the model to measure the relative cost of 

housing. No cost was inputed to owner equity 

Since it was assumed that most owners only 

20 
look at their monthly cost and consider their equity as an investment. 

The market share of each housing type 

was used as the dependent variable. SMSA’s 

without any mobile homes were eliminated. The 

logistic transformation was used to limit the 

range of the dependent variable. The following 

model was estimated (table 23): 

1n ( 1 

S

– 

1 

S ) = ß0 + ß1 C1 + ß2 C2 + ß3 C3 + μ1 

S1 = market share of housing type i 

average housing cost 

C1 = of housing type i 

average income 

μ1 = random error term 

i = 1 is single-family, 2 is multifamily, 

3 is mobile home 

Estimate of interarea price elasticities are 

summarized in table 24. The elasticity of 

family housing demand was about -0.4 relative 

to housing expenditures and -0.5 relative to 

house value. Mobile home elasticity was estimated to be positive at 0.86 and 1.20. This surprising result may reflect the fact that zoning 

restrictions often relegate mobile homes to lowcost areas; where zoning is more liberal, higher 

price units are placed on better sites. 

Time-Series Models of Housing

Production 

Time-series models can be constructed 

from annual data, quarterly data, or monthly 

data of housing production. Data have been 

collected on annual housing production by 

type of unit, including mobile homes, from 1947 

to 1977. Monthly and quarterly data are available from 1959 to the present. These data have 

also been collected and computerized. 

Data on economic and demographic variables have also been collected on an annual 

and quarterly basis. Regression analyses of annual changes in housing production have been 

conducted. Regression analyses have also 

been made on a quarterly basis. A monthly 

summary of housing production and market 

share by type of unit and region have also been 

computerized. The results of this work will be 

summarized later. 

Summary of Housing Choice 

This section reviewed factors affecting 

household housing choice between 

family, multifamily, and mobile home housing 

units and presented several econometric 

models of the relationship of some of these factors to housing choice. The purpose of this 

analysis is two-fold: (1) to establish the significance of these factors, and (2) to develop a formal analytic model for projecting housing 

choice in the housing model. 

Age of household head is the most important single determinant affecting the type of 

unit occupied. This partially is because age is a 

good proxy for many other factors such as income, assets, marital and family status, career 

position, and household attitude. Therefore, 

whenever possible other factors are related to 

age of household head. Household type is another important demographic variable of housing choice-marriedcouple, other family group, 

or individual household. Geographic factors of 

region of the country and location inside or outside metropolitan areas are also important. 

Economic factors such as household income 

and housing cost are also considered. 

Our housing model is based upon explicit 

consideration of population, headship, and 

housing type occupancy rates by age class. We 

want to retain this structure in developing an 

analytical model to project the future housing 

type-mix of the inventory and housing production. 

The model best suited for this approach is 

the individual household record model for each 

age group reported in tables 18-20. A simulation of housing projection has been conducted 

using this model; however problems have been 

arising in application of the model. 

Results of the models presented in this paper show that single-family housing occupancy 

is positively related to income. This relationship 

will eventually drive single-family housing to an 

unrealistically high proportion of housing in a 

model which assumes a constant increase in 

real family income. In addition cross-sectional 

models are not particularly good for forecasting time-series relationships. One possible improvement is to reformulate the equations us21 
ing income classes rather than a linear continuous income function. 

Mobile homes are extremely difficult to 

model because of the changing characteristics 

of the mobile home market and the evolution of 

mobile homes into a form of manufactured 

house. Mobile home occupancy fits poorly in 

the simulation based upon historical data. Mobile homes are over-estimated in the period 

from 1960 to 1970 and decrease rapidly in the 

period after 1990. Recent experience indicates 

that this relationship has changed since 1974 

and models based upon it will over-predict mobile homes market share. 

Simulation results using equations in tables 18-20 will be discussed in a later report. We 

feel this model with modification can be used 

for projecting housing types. Limits should be 

placed upon the housing occupancy rates by 

age and type of unit to assure the results will be 

reasonably consistent with past experiences. 

These should remain near the bounds of housing types defined in figure 6. For example, for 

the 35-44 and 45-54 age groups the maximum 

rate of single-family housing occupancy might 

be 85 percent, while the minimum multifamily 

rate could be 12 percent and mobile homes 3 

percent. In addition, the coefficient for income 

could be adjusted (arbitrarily for relative other 

models) to ameliorate the income effect. 

AN IMPROVED MODEL OF 

HOUSING REPLACEMENTS 

In the present model, units lost from the 

housing stock are estimated simply as a percentage of the housing inventory. A distinction 

is made for the rate of removal of conventional 

housing units and mobile homes because of 

the differences in their structure and longevity. 

Additionally, separate removal rates are estimated for each of the four census regions for 

conventional units. Thus, in the present model, 

four regional replacement rates are input for 

conventional housing units based on external 

analysis of census data, and one nationwide replacement rate is estimated for mobile homes 

which is based upon an analysis of changes in 

the mobile home inventory. 

To improve our estimates of housing replacement requirements and to attempt to develop behavioral relationships betweenthe rate 

of housing removal and economic variables 

such as economic growth, capital cost, housing prices, and housing operation cost, we attempted to: (1) Develop an annual series of 

"apparent" housing replacements derived 

from annual estimates of housing production, 

net household formations, and vacancy rates, 

and (2) to examine more closely changes in the 

housing inventory between past housing censuses to determine rates of replacements of 

housing units by type of structure and age of 

housing unit. 

A matrix of the housing stock based upon 

the type and age of housing units was estimated from Census data for 1940 to 1975. Removal rates were estimated for each cell based 

upon hypothesized average life cycle for each 

housing type. 

It appears that housing replacement demand is related to economic growth; however, 

it is questionable whether statistically sound 

econometric relationships can be estimated 

because of the lack of a primary data series for 

housing removals. For example, we know that 

net replacement of housing units was virtually 

nonexistent during the when economic

growth was low. 

In an attempt to establish time-series information, we will derive a series of apparent 

housing replacements based on the definition 

that all new housing production must be used 

for: (1) Additional households, or (2) additional 

vacancies or to replace units lost to the housing inventory. Apparent replacement will equal 

housing production minus the net increase in 

households minus vacancy changes minus a 

portion of mobile home shipments which are 

assumed not to be used as primary residences, 

i.e., as second homes or for nonresidential purposes. Specific series of annual housing replacement have been compiled; however, they 

have not provided useful information for developing statistical relationships. 

Long-term historical data by decade on 

housing removals from 1890 to 1960 were compiled in "Resources in America's Future" 

(Landsberg, Fischman, and Fisher, 1963).3 

Specific data on units lost from the housing 

stock can be found or derived from the Census 

of Housing for 1956, 1960, and 1970. Additional 

information on units lost from the housing inventory can also be obtained from the 1973 to 

3 MATERIAL IS SPECIFICALLY GIVEN IN TABLE A4-5, P. 621. 

22 
1975 Annual Housing Surveys. Data on gross 

housing replacement is also available from the 

annual housing surveys. General data on housing removals for the periods 1950 to 1956, 1956 

to 1960, 1960 to 1970, and 1970 to 1975 have 

been compiled (table 25). 

Estimates of the inventory of housing by 

age of structure are available beginning with 

the 1940 Census of Housing We have compiled 

a table of reported change by decade from 

1940 to 1970 and for 1970 to 1975. An average 

rate of annual disappearance was calculated 

based upon the reported change for the United 

States (table 26). 

We have calculated the rate of change of 

by housing type. Results of this comparison are somewhat erratic. For some periods, units appear to be added from previous 

reports. Multiunit structures can be added by 

conversion of existing units to apartments. In 

addition, errors in reporting age may occur, especially for older structures, The annual housing surveys are not strictly comparable in design to the Censuses, and the use of different 

weighting systems could distort direct comparison We have nevertheless developed a set of 

net replacement rates by type of unit for the 

United States and the four Census regions 

These are based upon reported changes in inventory by year built from 1960 to 1970 and 

1970 to 1974. A combination of the rates of 

change (sometimes positive) were used to derive a composite estimate of removals by age of 

structure 

These estimates of apparent replacement 

are then used to develop hypothetical life-cycle 

replacement curves of housing retirement by 

type of unit and region. A computer program 

has been developed to project replacement 

based upon these curves and to "grow" the 

housing inventory through time with new additions and removals. This submodel is intended 

to replace the current simple single replacement rate in the overall housing model. A summary of this program will be provided later after 

further refinement and it is incorporated into 

the housing projection model. 

The original model of housing demand was 

carefully formulated after considering and rejecting a number of economic variables which 

related to short-term influences on housing 

production These factors tended to obscure 

the impact of basic longrun demographic 

trends. Thus, the model was made simplistic 

purposely. Disaggregation of demand projections by housing type and region complicate 

the addition of economic variables because 

each factor must be coordinated in the regional 

and type projections. 

We are now reformulating our model. The 

improvements which have been implemented 

or are in the experimental state are: (1) New 

headship equations, (2) new housing choice 

equations, and (3) housing retirement matrix 

with age of structure, type of unit, and region 

Specific headship equations have been 

added. The housing occupancy equations 

listed in tables 18 to 20 are being programmed 

into the model for sensitivity testing. Mobile 

home choice may require an alternative model 

based upon time-series equations because of 

the dynamic nature of this market. A housing 

retirement matrix has been programed on an 

experimental basis and seems to give satisfactory results. It must still be incorporated into the 

general model. 

Future research areas of importance are 

the development of: (1) A model to relate housing retirement explicitly to alternative economic 

growth levels, (2) an explicit model of migration, 

(3) an improved model of housing size, and (4) 

a model of marital status and household composition. 

23 
LITERATURE CITED 

Atkinson, Jay L. 

1966. The purchase value of new houses. 

Survey of Current Business 43(11):8-19. 

Campbell, Burnham O. 

1966. Population change and building cycles. Bulletin Series, Bureau of Economics Business Research No. 91, 199 

p. Univ. Ill., Urbana. 

Carliner, Geoffrey. 

1974. Determinates of homeownership. 

Land Economics 1 (2):109-119. 

Davidson, Harold D. 

1973. Housing demand: mobile, modular, 

or conventional? Van Nostrand Reinhold Company, New York. 285 p. 

Drury, Margaret J. 

1972. Mobile homes: The unrecognized 

revolution in American housing. (Revised). Praeger publishers, 202 p. New 

York. 

Economic Report of the President. 

1977. U.S. Gov. Print. Off. 305 p. 

Grebler, Leo, and Sherman J. Maisel 

1963. Determinants of residential: A review of present knowledge. In Impacts 

of Monetary Policy, D. B. Suits et al. Research studies prepared for the Commission on Money and Credit. p. 475­

620. Englewood Cliff, N.J. Prentice-Hall. 

Landsberg, H., L. Fischman, and J. Fisher. 

1963. Resources in America’s future. 

John Hopkins Press, Baltimore, 1017 p. 

William, Eric Hirst, and Steve Cohn. 

1976. Fuel choices in the household sector. ORNL/CON-3, 41 p. Oak Ridge Nat. 

Lab., Oak Ridge, Tenn. 

Marcin, Thomas C. 

1972. Projections of demand for housing 

by type of unit and region. U.S. Dep. 

Agric. For. Serv. Agric. Hanb. 428. 76 

Professional Builder Magazine 

1977. 42(1):47 (Jan.). Cahners Publishing 

Co., Denver Colo. 

U.S. Department of Commerce, Bureau of 

the Census. 

1943. Sixteenth census of the United 

States: 1940, Report on Housing, Vol. 2, 

200 p. 

U.S. Department of Commerce, Bureau of 

the Census. 

1953. Census of housing: 1950, General 

Characteristics, part 1, U.S. Summary, 

147 p. 

U.S. Department of Commerce, Bureau of 

the Census. 

1963. U.S. Census of housing: 1960, 

HC(1)-1, U.S. Summary, 258 p. 

U.S. Department of Commerce, Bureau of 

the Census. 

1973. U.S. Census of housing: 1970, 

HC(1)-1, U.S. Summary, 270 p. 

U.S. Department of Commerce, Bureau of 

the Census. 

1975. Current housing reports, Series H150-73, Annual Housing Survey, 1973, 

Part A. 99 p. Append. 

U.S. Department of Commerce, Bureau of 

the Census. 

1976. Current housing reports, Series H150-73, Annual Housing Survey, 1974, 

Part A. 197 Append.

U.S. Department of Commerce, Bureau of 

the Census. 

1977. Current housing reports, Series H150-73, Annual Housing Survey, 1975, 

Part A. 203 Append.

U.S. Department of Commerce, Bureau of 

the Census. 

1977. Current construction report, Series 

C25, Characteristics of New One-family 

Houses, C25-76-14, 77 p. 

U.S. Department of Commerce, Bureau of 

the Census. 

1977. Current population report, Series P20, No. 313. Households and Families 

by Type. March. 6 

U.S. Department of Commerce, Bureau of 

the Census. 

1977. Projection of population of the 

United States 1977 to 2030, Series P-25, 

No. 704, 143 p. 

U.S. Department of Commerce, Bureau of 

the Census. 

24 
1978. Current construction report Series 

C20, Housing Starts, C25-78-4. 26p 

U.S. Department of Labor Bureau of Labor 

Statistics 

1977. Monthly labor review, various issues 

LIST OF TABLES 

1. U. S. Households by type for selected 

years, 1940 to 1977. 

2. Headship rates and the occurrence rates 

for husband-wife, other family and primary 

individual households by age class 1952 to 

1976. 

3. Population in various household types by 

sex and age: 1976 and estimates of alternative potential headship rates 

4. Population in various household types by 

sex and age: 1975 and estimates of alternative potential headship rates. 

5. Headship rates by age class in the United 

States for 1950, 1974 to 1976, and theoretical upper limit for headship. 

6. Regression equations for relating headship to real per capita personal income by 

age class using the logistic function 

7. Headship rate projections by age class for 

1 and 2 percent growth in real disposable 

income for 1980 to 2020. 

8. Distribution of housing inventory by type of 

unit for 1940, 1950, 1960, 1970, and 1973 

to1976. 

9. A comparison of reported mobile home 

shipments, with subsequent inventory 

counts for 1960, 1970, 1973, and 1975. 

10. The occupied housing inventory by tenure 

and by type of unit for 1940, 1950, 1960, 

1970, and 1973 to 1976 

11. Regression analysis of the probability of a 

household living in an apartment in 1973. 

12. Regression analysis of the probability of 

living in a single-family house, an apartment, or a mobile home in 1975. 

13. The distribution of housing types by age 

class within the home ownership and rental 

markets for 1960, 1970, and 1973 to 1975. 

14. Home ownership by housing type and age 

class for 1960, 1970, and 1973 to 1975. 

15. Renter-occupied housing by type of unit 

and age class for 1960, 1970, and 1973 to 

1975. 

16. The distribution of housing inventory by 

type of unit for United States and regions for 1940, 1950, 1960, 1970, and 1973 

to 1975. 

17. Percentage of households living in multiunit houses. 

18. Regression coefficients for single-family 

housing occupancy by age class, 1976. 

19. Regression coefficients for apartments 

(two or more units) occupancy by age 

group, 1976. 

20. Regression coefficients for mobile home 

occupancy by age class, 1976. 

21. Mean values of variables used in housing 

occupancy regression analysis by age 

group, 1976. 

22. State cross-sectional regression model of 

housing occupancy, with estimated coefficients, semilog model, 1970. 

23. Cross-sectional SMSA regression mode! 

for housing-type occupancy, semilog 

model, 1975. 

24. Elasticity of housing types relative to housing costs based upon 1970 state model and 

1975 SMSA model. 

25. Annual net replacement rates for conventional housing and all housing including 

mobile homes in the United States by regions for 1950-1956, 1960-1969 and 1970­

1975. 

26. United States housing inventory by age of 

structure (year built) for 1940, 1950, 1960, 

1970, and 1975 with estimates of annual 

disappearance. 

25 
Table 1.–U.S. households by type for selected years, 1940 to 1977 

Year All 

households 

Husband-wife 

Number Percent 

Other family 

Number Percent 

Primary individual 

Number Percent 

1940 34,949 26,571 76.0 4,920 14.1 3,458 9.9 

1947 39,612 39,612 78.3 4,352 11.1 4,143 10.6 

1950 43,554 34,075 78.2 4,763 10.9 4,716 10.8 

1955 47,874 36,251 75.7 5,481 11.5 6,142 12.8 

1960 52,799 39,254 74.3 5,650 11.8 7,895 16.5 

1965 57,436 41,689 72.6 6,149 10.7 9,598 16.7 

1970 63,401 44,728 70.5 6,728 10.6 11,495 18.8 

1975 71,120 46,951 66.1 8,612 11.9 15,557 22.0 

1976 72,867 47,297 64.9 8,759 12.0 16,811 23.1 

1977 74,142 47,471 64.0 9,001 12.2 17,669 23.8 

Source: U.S. Department of Commerce, Bureau of the Census: Current Population Report, Series P-20. No. 313. 

Table 2.–Headship rates and occurence rates for husband-wife, other family, and primary individual households by age class 1952 to 1976 (percent) 

Age class 

18-24 25-29 Year 

Headship Husband-wife Other Primary Other Primary 

family individual Headship Husband-wife family individual 

1952 12.9 

1953 13.6 

1954 12.8 

1955 14.2 

1956 15.1 

1957 15.4 

1958 15.6 

1959 16.0 

1960 15.8 

1961 15.5 

1962 16.3 

1963 15.8 

1964 16.4 

1965 17.0 

1966 16.7 

1967 15.9 

1968 16.7 

1969 17.2 

1970 17.6 

1971 18.4 

1972 19.9 

1973 20.7 

1974 21.7 

1975 21.2 

1976 20.9 

10.7 0.9 1.3 36.0 32.0 2.1 1.8 

11.3 1.0 1.3 36.0 32.0 2.2 1.7 

10.1 .9 1.8 35.0 30.7 2.4 1.9 

12.0 1.1 1.1 34.4 30.0 2.5 2.1 

12.6 1.2 1.3 36.7 32.4 2.3 1.9 

12.3 1.4 1.6 36.8 32.6 2.5 1.7 

12.7 1.3 1.6 37.7 32.9 2.5 2.3 

13.2 1.0 1.8 37.8 32.9 2.6 2.3 

13.0 1.1 1.8 39.2 34.2 2.7 2.4 

12.2 1.3 2.0 39.7 34.3 2.5 2.9 

12.8 1.3 2.2 40.0 33.6 3.1 3.3 

12.6 1.2 2.0 40.1 33.4 3.5 3.2 

12.9 1.5 2.0 40.8 35.0 3.1 2.8 

13.4 1.2 2.4 42.5 36.0 3.3 3.2 

13.1 1.2 2.4 43.1 35.9 3.6 3.7 

12.1 1.2 2.5 44.0 36.9 3.3 3.9 

12.3 1.4 3.1 42.1 35.0 3.3 3.8 

12.4 1.5 3.3 44.5 35.9 4.0 4.7 

12.3 1.8 3.5 44.9 36.2 3.8 5.0 

12.5 1.9 3.9 44.7 34.6 4.4 5.6 

12.8 2.3 4.8 46.2 35.7 4.2 6.3 

13.1 2.6 5.1 46.7 34.4 5.3 6.9 

13.1 2.5 6.1 46.9 33.5 5.2 8.2 

12.2 2.8 6.1 46.8 33.1 5.3 8.4 

11.4 2.8 6.7 47.4 32.2 5.2 10.0 

26 
Table 2.–Headship rates and occurrence rates for husband wife other family, and primary individual households by age class 1952 to 1976 (percent) continued 

Age class 

30-34 35-44 Year 

Other Primary Other Primary Headship Husband-wife Headship Husband-wife family individual family individual 

1952 41.5 37.5 2.7 1.3 46.1 39.0 4.3 2.9 

1953 42.9 38.0 3.0 1.9 45.8 39.0 3.7 3.1 

1954 43.8 38.5 3.2 2.2 47.0 39.8 4.5 2.7 

1955 42.1 37.1 3.3 1.7 48.1 40.3 4.9 2.9 

1956 41.7 35.8 3.2 1.7 46.9 39.8 4.7 2.5 

1957 42.8 38.0 2.9 1.9 46.7 40.1 4.3 2.3 

1958 43.2 38.1 3.0 2.1 46.6 39.7 4.2 2.7 

1959 44.1 38.6 3.3 2.2 47.2 40.0 4.4 2.8 

1960 44.8 39.1 3.3 2.5 47.9 40.5 4.7 2.8 

1961 45.2 38.7 3.7 2.8 47.4 39.8 4.6 2.9 

1962 46.5 39.6 4.0 2.9 48.1 40.4 4.7 3.0 

1963 46.4 40.0 3.9 2.5 48.8 41.2 5.0 2.6 

1964 45.9 39.9 3.6 2.4 49.4 41.1 5.3 3.0 

1965 46.1 39.4 3.9 2.7 48.9 40.0 5.4 3.5 

1966 46.1 39.0 4.0 3.1 48.9 40.4 5.2 3.3 

1967 46.2 38.8 4.4 3.1 49.5 40.7 5.4 3.4 

1968 47.8 40.2 4.6 3.1 50.2 41.0 5.6 3.6 

1969 48.1 40.0 4.4 3.7 50.1 40.9 5.8 3.4 

1970 48.3 40.5 4.3 3.5 50.4 41.3 5.5 3.5 

1971 48.1 39.0 5.3 3.8 51.0 40.8 6.1 4.0 

1972 50.1 39.2 5.6 4.7 50.5 39.9 6.6 4.0 

1973 50.5 39.8 6.3 4.6 51.6 40.4 6.8 4.5 

1974 51.0 39.5 5.9 5.7 51.4 39.7 7.3 4.4 

1975 51.6 38.7 6.5 6.4 52.0 39.7 7.8 4.5 

1976 50.9 37.3 7.0 6.6 53.2 40.2 8.0 5.0 

27 
Table 2.–Headship rates and occurrence rates for husband wife, other family, and primary individual households by age class 1952 to 1976 (percent) continued 

Age class 

45-54 55-64 Year 

Other Primary Other Primary 

Headship Husband-wife family individual Headship Husband wife family individual 

1952 50.4 

1953 52.1 

1954 51.1 

1955 50.8 

1956 51.3 

1957 52.2 

1958 53.5 

1959 52.9 

1960 52.9 

1961 51.6 

1962 51.7 

1963 51.5 

1964 52.3 

1965 52.4 

1966 52.8 

1967 52.4 

1968 52.4 

1969 52.6 

1970 52.6 

1971 53.5 

1972 54.2 

1973 54.1 

1974 54.4 

1975 54.3 

1976 54.2 

40.1 

58.3 

38.8 6.2 5.4 55.7 39.1 7.5 9.0 

40.0 6.1 6.0 55.3 37.1 7.6 10.6 

40.0 5.6 5.6 53.9 37.6 7.1 9.2 

40.0 5.9 5.0 54.3 37.7 7.2 9.4 

39.8 6.1 5.4 55.4 38.5 7.1 9.9 

40.8 6.1 5.4 55.2 38.4 6.7 10.1 

41.2 6.4 5.9 54.1 37.2 6.5 10.5 

40.6 6.1 6.3 54.4 36.9 6.3 11.2 

40.9 6.2 5.8 55.1 37.6 6.3 11.2 

5.9 5.6 56.9 39.0 6.4 11.5 

40.5 5.6 5.6 56.4 38.5 6.4 11.5 

40.3 5.7 5.5 55.8 38.3 6.4 11.1 

40.9 5.8 5.6 56.1 38.4 6.1 11.7 

40.9 6.2 5.4 56.7 38.2 6.2 12.4 

41.1 5.9 5.9 56.3 37.9 5.7 12.6 

40.1 6.2 5.4 56.3 38.2 5.7 1.24 

40.6 6.0 5.8 58.1 39.3 6.0 12.8 

40.3 5.9 6.5 58.3 39.7 5.7 12.9 

40.6 6.0 6.1 58.0 38.8 6.1 13.1 

40.5 6.7 6.3 58.2 39.2 5.8 13.2 

41.2 6.5 6.5 58.5 39.3 6.0 13.2 

41.0 6.5 6.6 58.3 38.9 6.1 13.2 

40.7 6.6 7.2 57.3 38.4 6.0 12.9 

40.1 7.1 7.1 57.4 37.9 6.1 13.4 

40.1 6.8 7.2 38.7 6.1 13.6 

28 
Table 2.–Headship rates and occurrence rates lor husband wife, other family, and primary individual households by age class 1952 to 1976 (percent) continued 

Age class 

65 and older Year 

Headship Husband-wife Other Primary 

family individual 

1952 54.3 

1953 56.1 

1954 54.2 

1955 54.7 

1956 55.2 

1957 54.5 

1958 54.8 

1959 55.6 

1960 56.8 

1961 56.2 

1962 59.8 

1963 60.0 

1964 59.7 

1965 60.5 

1966 61.1 

1967 62.1 

1968 62.0 

1969 62.1 

1970 61.5 

1971 61.8 

1972 63.7 

1973 63.5 

1974 64.1 

1975 64.4 

1976 65.0 

29.4 9.6 15.0 

29.7 9.7 16.7 

29.7 8.7 15.7 

28.4 9.0 17.3 

28.9 9.1 17.2 

28.1 9.5 16.9 

28.2 8.8 17.9 

28.6 8.7 18.4 

29.1 8.3 19.4 

28.7 8.0 19.5 

30.8 8.1 20.9 

30.4 8.3 21.3 

29.8 8.2 21.7 

29.2 8.0 23.3 

29.6 8.0 23.5 

29.7 8.0 24.4 

29.5 7.6 24.9 

28.9 7.6 25.5 

28.3 7.2 26.0 

28.7 6.5 26.7 

29.3 6.6 27.8 

28.7 7.0 27.7 

29.8 6.6 27.7 

30.1 6.2 28.1 

29.6 6.2 29.2 

Source U.S. Department of Commerce, Bureau of the Census. Current Population Report, Series P-20 and P-25; various issues. 

29 
Table 3.–Population in various household types by sex and age: 1976 and estimates of alternative potential headship rates 

(Thousands excluding inmates in institutions and persons living in group quarters.) 

Subject Age class 

18-24 25-29 30-34 35-44 45-54 55-64 65 and over 

Male, total 13,156 8,465 6,801 11,107 11,296 9,320 8,913 

Household head, wife present 3,189 5,641 5,286 9,239 9,496 7,713 6,730 

Other family 98 90 85 266 347 238 229 

Primary individual 1,064 1,088 635 743 758 849 1,398 

Child of head (not in subfamily. 18-24 only) 7,486 – – – – – – 

Female, total 13,780 8,754 7,128 11,712 12,156 10,447 12,749 

Wife of household head 5,223 8,246 5,509 9,205 9,361 7,000 4,600 

Household head, other family 669 813 903 1,576 1,273 970 1,121 

Primary individual 818 667 302 403 945 1,862 5,254 

Child of head (not subfamily, 18-24 only) 5,415 – – – – – – 

Population in husband wife households 8,412 11,887 10,795 18,444 18,857 14,713 11,330 

Children of heads (18-24) 12,901 – – – – – – 

Population in households 26,936 17,219 13,929 22,819 23,452 19,767 21,662 

Not married couples or children of head (18-24) 5,623 5,336 3,134 4,375 4,595 5,054 10,332 

Husband wife households 3,189 5,641 5,286 9,239 9,496 7,713 6,730 

80 percent of other population 4,498 4,269 2,507 3,500 3,676 4,043 8,266 

Total population1 27,982 17,509 14,161 22,989 23,670 19,951 22,758 

Potential headship percent with 80 percent headship for 

nonhusband-wife population 27.5 56.6 55.0 55.4 55.6 58.9 65.9 

Potential headship, percent, with 90 percent headship for 

nonhusband-wife population 29.5 59.6 57.2 57.3 57.6 61.5 70.4 

Percent of male household heads with wife present–1976 11.4 32.2 37.3 40.2 40.1 38.7 29.6 

Potential headship assuming a 10 percent decline in 

husband wife households and 80 percent nonhusbandwife headship 28.2 58.5 57.2 57.8 58.0 61.2 67.7 

Potential headship assuming a 10 percent decline in 

husband wife households and 90 percent nonhusband 

wife headship 30.4 62.2 60.2 60.5 60.8 64.6 72.8 

inmates and armed forces overseas 

30 
4–Population in various household types by sex and age: 1975 and estimates of alternative potential headship rates 

(Thousands excluding inmates in institutions and persons living in group quarters.) 

Ageclass 

Subject 

18-24 25-29 30-34 35-44 45-54 55-65 65 and over 

Male, total 

Household head wife present 

Other family 

Primary individual 

Child of head (not in subfamily, 18-24 only) 

female, total 

Wife of household head 

Household head other family 

Primary individual 

Child of head (not in subfamily, 18-24 only) 

Population in husband wife households 

Children of heads (18-24) 

Population in households 

Not married couples or children of head (18-24) 

Husban-wife households 

80 percent of other population 

Total population1 

Potential headship, percent, with 80 percent headship for 

nonhusband-wife population 

Potential headship, percent, with 90 percent headship for 

nonhusband-wife population 

Percent of male household heads with wife present 1975 

Potential headship assuming a 10 percent decline in 

husband-wife households and 80 percent nonhusband 

wife headship 

Potential headship assuming a 10 percent decline in 

husband wife households and 90 percent nonhusband 

wife headship 

12,833 8,048 6,728 10,992 11,366 9,181 8,722 

3,352 5,525 5,354 9,060 9,544 7,451 6,656 

237 117 96 279 353 276 267 

975 868 572 668 704 770 1,346 

7,051 – – – – – – 

13,484 8,345 6,971 11,615 12,220 10,305 12,405 

5,367 6,106 5,434 9,207 9,279 6,823 4,589 

685 764 808 1,497 1,326 930 1,107 

693 536 308 356 988 1,875 4,884 

5,367 – – – – – – 

8,719 11,631 10,788 18,267 18,823 14,274 11,245 

12,418 – – – – – – 

26,317 16,393 13,699 22,607 23,586 19,486 21,127 

5,180 4,762 2,911 4,340 4.763 5,212 9,882 

3,352 5,525 5,354 9,060 9,544 7,451 6,056 

4,144 3,810 2,329 3,472 3,810 4,170 7,906 

27,387 16,705 13,844 22,823 23,787 19,696 22,208 

27.4 55.9 55.5 54.9 56.1 59.0 65.6 

29.3 58.7 57.7 56.8 58.1 61.6 69.9 

12.2 33.1 38.7 39.7 40.1 37.8 30.0 

28.1 57.9 57.8 57.3 58.5 61.3 67.5 

30.3 61.5 60.8 59.8 61.3 64.6 72.3 

1 Includes inmates and armed forces overseas 

31 
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 

Table 5.–Headship rates by age class in the United States for 1950, 1954 to 1976, and theoretical upper limit for headship 

Age class 

Year 18-24 25-29 30-34 35-44 45-54 55-64 65 and over 

1950 13.1 33.9 39.9 44.8 49.2 52.0 52.8 

1954 12.7 35.4 42.7 47.2 51.4 53.7 55.5 

1955 14.2 34.8 43.7 48.2 50.8 54.2 54.7 

1956 15.1 37.1 42.0 47.1 51.2 53.4 55.2 

1957 15.4 37.2 43.0 46.9 52.1 55.2 55.0 

1958 15.6 38.1 43.4 47.0 53.6 54.1 54.8 

1959 16.0 38.2 44.3 47.3 52.8 54.5 55.6 

1960 15.8 39.3 44.9 48.0 53.0 54.7 56.8 

1961 15.5 39.6 45.2 47.6 52.3 56.9 56.1 

1962 16.3 40.0 46.5 48.0 51.4 56.4 59.7 

1963 15.8 40.1 46.4 48.8 51.6 55.8 60.0 

1964 16.4 40.9 45.9 49.4 51.5 56.1 59.7 

1965 17.0 42.5 46.1 48.9 52.8 56.7 60.5 

1966 16.7 43.1 46.1 48.9 52.8 56.5 61.0 

1967 15.9 44.0 46.2 49.5 52.4 56.3 61.2 

1968 16.7 42.2 48.0 50.3 52.5 58.0 62.4 

1969 17.2 43.9 48.3 50.3 52.9 58.3 62.7 

1970 17.6 44.5 48.8 50.7 52.7 58.3 62.9 

1971 18.3 44.5 48.3 51.4 53.9 58.5 62.3 

1972 19.9 44.0 49.5 50.6 54.2 58.5 64.1 

1973 20.7 46.0 50.6 51.6 54.1 58.3 64.3 

1974 21.7 46.5 51.2 51.1 54.7 57.2 64.3 

1975 21.2 46.8 51.6 52.0 54.3 58.4 64.4 

1976 20.9 47.4 50.9 53.2 54.2 58.3 65.0 

Upper 

limit 30.0 56.0 56.0 57.0 58.0 60.0 68.0 

Source: U.S. Department of Commerce, Bureau of the Census, Current Population Report, Series P-25 and Series P-20, varous issues 

Table 6.–Regression equations for relating headship to real per capita personal incme by age class using the logistic function 

Headship Age class upper limit Regression equation1 

18-24 0.30 

25-29 .56 

30-34 .56 

35-44 .57 

45-54 .58 

55-64 .60 

65 and .68 

over 

1The equations were fit for annual data from 1953 to 1976, where: 

H = 1n( ) on the logistic transformation for headship a - Hn 

H 

a = an estimated upper limit for headship 

Y = disposable personal income 

(consumer price index) (population 18 and older) 

Data sources Headship rates from Economic Report of the President, 1977, table 5: population 18 and older from U.S. Department of Commerce, Bureau of Census, 

Series P-20 

32 
Table 7.—Headship rate projections by age class for 1 and 2 perce3nt growth in real disposable personal income (DPI) for 1980 to 2020 

Age class 

Year 18-24 25-29 30-34 35-44 45-54 55-64 65 and over 

1 PERCENT GROWTH IN REAL DPI PER ADULT 

1980 20.9 47.7 51.2 54.0 54.2 58.4 65.4 

1985 21.4 48.8 51.9 54.7 54.5 58.6 65.8 

1990 22.0 49.8 52.5 55.3 54.8 58.9 66.3 

1995 22.6 50.7 53.1 55.8 55.1 59.1 66.7 

2000 23.3 51.5 53.6 56.1 55.3 59.2 67.0 

2005 23.9 52.2 54.0 56.4 55.6 59.4 67.3 

2010 24.5 52.9 54.4 56.6 55.8 59.5 67.5 

2015 25.1 53.5 54.7 56.7 56.1 59.6 67.6 

2020 25.6 54.0 55.0 56.8 56.3 59.7 67.7 

2 PERCENT GROWTH IN REAL DPI PER ADULT 

1980 21.1 48.3 51.4 54.0 54.3 58.5 65.5 

1985 22.1 50.2 52.6 54.9 54.9 59.0 66.3 

1990 23.3 51.9 53.6 55.6 55.4 59.3 67.0 

1995 24.5 53.2 54.4 56.1 55.9 59.6 67.5 

2000 25.7 54.2 55.0 56.5 56.3 59.7 67.7 

2005 26.7 54.9 54.4 56.7 56.7 59.8 67.9 

2010 27.6 55.3 55.7 56.0 57.0 59.9 67.9 

2015 28.3 55.6 55.8 56.9 57.3 60.0 68.0 

2020 28.8 55.8 55.9 57.0 57.5 60.0 68.0 

Table 8.—Distribution of housing inventory by type of unit for 1940, 1950, 1960, 1970, and 1973 to 1976 

One-family 

Year Detached 

houses 

One-family 

unit1 

Mobile home 

or trailer 

plus 

mobile 

Multifamily 

unit 

homes 

Pct Pct Pct Pct Pct 

1940 66.7 2 71.2 30.4 71.6 28.4 

1950 64.0 268.5 .7 69.3 29.7 

1960 68.8 74.1 1.3 76.3 23.7 

1970 66.2 69.1 3.1 72.2 27.8 

19734 63.7 68.1 4.4 72.5 27.5 

19744 63.6 67.6 4.9 72.5 27.3 

19754 64.2 68.3 4.3 72.6 27.4 

19765 N.A. 68.0 4.5 72.5 27.4 

1Includes attached one-unit structures. 

2Includes two-family side-by-side which are clasified as one-unit attached after 1960. 

3Includes trailers and other miscellaneous temporary housing. 

4 The annual housing includes adjustments of 700,000, 400,000 and 200,000 additional mobile home for 1973, 1974, and 1975, respectively, because of a lack of a 

sampling procedure for new mobile home parks. An additional 600,000 conventional units were added to account for units started before January 1, 1970, and not 

included in the sampling procedure for new permits. For details see the appendix sections of the Annual Housing Reports. While concepts and definition are 

generally compatable between the 1970 census and the 1973, 1974, and 1975 housing surveys, year-to-year comparison should be made with caution because of 

differences in sample size and enumeration methods. The 1974 and 1975 questionnaire and sample size differ slightly from 1973's. 

5 Preliminary data. 

Source: U.S. Department of Commerce, Bureau of the Census, 1940, 1950, and 1970 Censuses of Housing; 1973 to 1976 Annual Housing Surveys. 

33 
Table 9.– A comparison of reported mobile home shipments, with subsequent inventory counts for 1960, 1970, 1973, and 1975 

Count of Mobile home Primary households 

Year shipments homes occupied as a percent of as primary reported 

households 

1960 CENSUS 

1955-1958 

1959-March 1960 

457 

132 

251 

106 

54.9 

80.3 

1970 CENSUS 

1960-1964 

1965-1968 

1969-March 1970 

654 

990 

513 

469 

708 

335 

71.7 

71.5 

65.3 

1973 SURVEY 

1960-1964 654 376 57.5 

1965-1968 990 646 65.3 

1969-June 19731 2,285 1,312 57.4 

1969 June 19732 2,285 2,012 88.1 

1975 SURVEY 

1960-1964 

1965-1968 

1969-June 19753 

654 

990 

2,890 

291 

555 

2,153 

44.5 

56.1 

74.5 

1Based on unweighted count from public use sample tape of entire survey 

2With an arbitrary adjustment of an additional 700,000 mobile homes for assumed undercounting. 

3With an arbitrary adjustment of an additiondl 200,000 units for assumed undercounting. 

Source US Department of Commerce Bureau of the Census, Series C-20; various issues and data compiled from sample survey data tapes 

Table 10. –The occupied housing inventory by tenure and by type of unit for 1940, 1950, 1960, 1970, and 1973 to 1976 

Owner occupied Renter occupied1 

Year Owners Mobile Mobile One unit Multiunit One unit Multiunit home home 

Pct Pct Pct Pct Pct Pct Pct 

1940 43.6 89.3 10.3 20.4 56.9 42.6 20.5 

1950 55.0 88.1 10.8 1.1 44.7 55.0 .3 

1960 62.2 87.2 10.7 2.1 48.2 51.4 .4 

1970 62.9 89.0 6.6 4.4 36.2 62.4 1.4 

1973 64.4 87.7 6.0 6.3 34.2 63.9 1.9 

1974 64.6 87.4 5.7 6.9 33.7 64.1 2.2 

1975 64.6 88.2 5.8 6.0 32.9 65.1 2.0 

1976 64.8 87.9 5.8 6.3 32.5 65.0 2.5 

1lncludes units with no cash rent 

2lncludes all other temporary housing 

Source US Department of Commerce, Bureau of the Census, 1940, 1950, 1960, and 1970 Censuses of Housing; 1973-1976 Annual Housing Surveys. 

34 
Table 11.– Regression analysis of the probability of a household living in an apartment in 19731 

Mean Regression value Aggregate Mean 

value Aggregate 

coefficient2 effect effect 1973 1990 

Constant 0.6465 0.6465 0.6465 

of persons -.0329 2.97 -.0977 2.65 -.0813 

Income -.0000031 11,205 -.0347 14,460 -.0448 

Household type 

Husband wife -.2010 .6708 -.1348 .5893 -.1184 

One parent -.0978 .1144 -.0112 .1228 -.0120 

Primary individual reference .2148 — .2879 – 

Region 

Northeast .2238 .2340 .0524 .2101 .0470 

North Central .0594 .2727 .0162 .2481 .0147 

South reference .3116 — .3372 

West .0532 .1817 .0096 .2046 .0109 

Metropolitan location 

in central city .2086 .3143 .0656 .2800 .0584 

in SMSA outside city reference .3680 — .3800 

-.0895 .3177 -.0284 .2400 -.0304 

Age class 

18-24 reference .0817 .0653 

25-29 -.0965 .1042 -.0101 .1114 -.0108 

30-34 -.1804 .0950 -.0171 .1200 -.0216 

35-44 -.2194 .1733 -.0380 .2210 -.0485 

45-54 -.2729 .1857 -.0507 .1492 -.0407 

55-64 -.3019 .1671 -.0504 .1297 -.0392 

65 and over -.3086 .1930 -.0596 .2061 -.0636 

Probability of living in apartment = 0.2576 in 1973 and 0.2602 in 1990. 

Proportion of inventory in multiunit structures3 = 0.275 in 1973 and 0.277 in 1990. 

Multiple correlation coefficient = 0.527. 

Coefficient of determination = 0.278. 

ratio = 1200.7 with 15 and 46,790 deg. Freedom. Sign at 0.00001 level. 

1Single family house attached units while all structures with two or more units as defined by the Census Bureau are considered apartments lor this table 

2Based on the 1973 Annual Housing Survey. All regression coefficients are significant at 0.00001 level based upon t-value test with 46,190 deg. Freedom 

of 3Estimates of proportion of the housing inventory in multiunit structures differs from estimated relationship for living in an apartment because of vacant

units from the regression analysis and the use of the unweighted survey data. 

35 
Table 12.– Regression analysis of the probbility of lining in a single-family house, an apartment, or a mobile home in 1975 

Independent variable 

Housing type 

Mobile home One-unit house Apartments, two 

or more units 

Dependent variable 

Constant 0.13936 0.36019 0.50044 

Age class 

18-24 reference reference reference 

25-29 -.02092 .12465 -.10373 

30-34 -.01662 .23278 -.21616 

35-44 -.02116 .28034 -.25918 

45-54 -.03151 .35156 -.32005 

55-64 -.02606 .40075 -.37475 

65 and over -.03705 .41486 -.37781 

Household type 

Husband-wife reference reference reference 

Other family -.02515 -.09988 .12503 

Individuals -.03577 -.19431 .23008 

Region 

Northeast -.02233 -.14367 .16600 

North Central -.01546 -.01061 .02607 

South reference reference reference 

West +.04929 -.05818 .00889 

Metropolitan location 

In central cities -.04850 -.14448 -.19298 

In SMSA-outside city reference reference reference 

Non-SMSA .03324 .03976 -.07300 

Number of persons -.01011 .04815 -.03803 

Income -0.1375 .03954 -.02579 

Expendutures-to-income -.00011 -.00176 .00188 

Coefficient of 

determination, R2 .09 .75 .50 

36 
Table13.–The distribution of housing types by age class within the home ownership and rental markets for 1960, 1970, and 1973-1975 

(Percent of households) 

Age class Housing type 

Under 25 25-29 30-34 35-44 45-54 55-64 65-74 75 and over 

OWNERS-1960 

Single family 0.80 0.92 0.93 0.94 0.93 0.91 0.88 0.88 

Multifamily .04 .03 .04 .04 .06 .08 .10 .10 

Mobile home .16 .05 .03 .01 .01 .01 .01 .02 

OWNERS-1970 

Single family .70 .84 .93 .93 .92 .89 .86 .84 

Multifamily .05 .05 .03 .04 .06 .08 .10 .13 

Mobilehome .26 .11 .05 .03 .02 .03 .04 .03 

OWNERS-1973 

Singlefamily .66 .84 .90 .94 .93 .88 .87 .86 

MuItifamily .06 .05 .04 .03 .04 .07 .08 .10 

Mobile home .28 .11 .06 .03 .03 .04 .05 .04 

OWNERS-1974 

Singlefamily .59 .82 .89 .92 .91 .88 .85 .84 

Multifamily .04 .05 .03 .04 .04 .07 .09 .11 

Mobilehome .37 .14 .08 .05 .04 .05 .06 .05 

OWNERS-1975 

Single family .63 .83 .90 .92 .92 .88 .86 .84 

Multifamily .04 .05 .03 .04 .04 .07 .08 .11 

Mobile home .32 .12 .07 .04 .04 .05 .05 .05 

RENTALS-1960 

Single family 0.48 0.52 0.53 0.52 0.48 0.42 0.41 0.42 

Multifamily .51 .48 .47 .47 .52 .58 .59 .57 

Mobilehome .01 .00 .00 .00 .00 .00 .01 .01 

RENTALS-1970 

Single family .28 .37 .46 .44 .39 .33 .30 .29 

MuItifamily .69 .61 .53 .55 .60 .66 .69 .70 

Mobilehome .03 .02 .01 .01 .01 .01 .01 .01 

RENTALS-1973 

Singlefamily .31 .34 .39 .43 .38 .36 .31 .30 

Multifamily .66 .64 .59 .56 .60 .63 .68 .69 

Mobilehome .03 .02 .02 .02 .02 .01 .01 .01 

RENTALS-1974 

Single family .29 .33 .38 .41 .35 .38 .29 .29 

Multifamily .68 .65 .60 .57 .63 .61 .70 .69 

Mobilehome .04 .02 .02 .02 .02 .01 .01 .02 

RENTALS-1975 

Single family .28 .31 .36 .41 .37 .35 .27 .27 

Multifamily .69 .66 .61 .57 .61 .64 .71 .12 

Mobilehome .03 .02 .02 .02 .01 .01 .01 .01 

Source U.S. Bureau ofthe Census: One in 1,000 Public Use Sample Tapefrom the 1960 and 1970 Census: Public Use Sample Tape from the 1973-1975Annual Housing 

Surveys. 

37 
Table 14.–Home ownership by housing type and age class for 1960, 1970, and 1973 to 1975. 

(Percent of all households.) 

Ageclass 

House type Under 75 and All 

25 

25-29 30-34 35-44 45-54 55-64 65-74 over households 

OWNERS–1960 

Single family 17.5 35.7 53.0 62.6 63.2 61.6 61.2 60.8 56.9 

Multifamily .9 1.3 2.4 2.8 4.1 5.2 7.0 7.1 3.9 

Mobile home 3.5 1.9 1.6 .9 .9 1.0 1.0 1.1 1.2 

Total 21.9 38.9 57.0 66.3 68.2 67.8 69.2 69.0 62.0 

OWNERS–1970 

Single family 14.4 35.2 53.7 64.4 67.7 63.7 59.1 55.6 56.1 

Multifamily 1.0 2.0 2.0 2.7 4.0 5.5 6.9 8.7 4.1 

Mobile home 5.3 4.4 2.9 1.9 1.8 2.3 2.0 2.3 2.7 

Total 20.7 41.6 58.6 69.0 73.5 71.6 68.0 66.6 62.8 

OWNERS–1973 

Single family 14.6 36.4 54.8 66.8 71.2 67.4 62.1 57.4 57.9 

Multifamily 1.4 2.2 2.2 2.5 3.4 5.5 6.1 6.6 3.6 

Mobile home 6.1 5.0 3.5 2.1 2.2 3.3 3.6 2.4 3.2 

Total 22.1 43.6 60.5 71.4 76.8 76.2 71.8 66.4 64.6 

OWNERS–1974 

Single family 13.3 35.0 54.6 65.5 69.7 67.3 61.0 55.9 56.5 

Multifamily .8 2.0 2.1 2.6 3.4 5.2 6.2 7.4 3.7 

Mobile home 8.4 5.9 4.9 3.5 3.2 3.8 4.4 3.6 4.4 

22.5 42.9 61.6 71.6 76.3 76.3 71.6 66.9 64.6 

OWNERS–1975 

Single family 12.9 35.8 56.0 65.7 70.7 68.1 61.6 56.4 57.0 

Multifamily .9 2.1 1.9 2.6 3.5 5.2 6.4 7.8 3.8 

Mobile home 6.6 5.3 4.3 3.2 3.0 3.6 3.9 3.1 3.9 

20.4 43.2 62.3 71.5 77.2 76.9 71.9 67.3 64.7 

Source: U.S. Bureau of the Census: One in 1,000 Public Use Sample Tapes from 1960 and 1970 Census; Public Use Sample Tape from 1973-1975 Annual Housing 

Surveys. 

38 
Table 16.–The distribution of the housing inventory by type of unit for the United States and regions for 1940, 1950, 1960, 1970 and 1973 to 1975 

Region 

Year Housing type 

Northeast North 

Central South West United 

States 

Pct Pct Pct Pct Pct 

1940 Single family 51.7 71.8 85.4 77.6 71.2 

1950 Single family 51.9 70.3 80.9 75.6 68.5 

1960 Single family 57.8 77.4 86.2 78.6 74.1 

1970 Single family 54.2 71.9 77.7 70.0 69.1 

1973 Single family 55.3 71.2 75.7 66.7 68.1 

1974 Single family 55.4 71.3 74.0 66.1 67.6 

1975 Single family 55.5 71.3 74.2 66.8 67.8 

1940 Mobile home .2 .4 .4 1.2 .4 

1950 Mobile home .2 .8 .6 1.6 .7 

1960 Mobile home .7 1.3 1.7 2.7 1.3 

1970 Mobile home 1.5 2.7 4.2 3.9 3.1 

1973 Mobilehome 2.1 3.6 6.2 5.1 4.4 

1974 Mobile home 2.2 3.9 7.0 6.1 4.9 

1975 Mobile home 1.9 3.5 5.9 5.6 4.3 

1940 Multifamily 48.1 27.8 14.2 20.2 28.4 

1950 Multifamily 48.9 28.9 18.5 22.8 29.7 

1960 Multifamily 41.5 21.3 12.5 18.8 23.7 

1970 Multifamily 44.3 25.4 18.1 26.2 27.8 

1973 Multifamily 42.6 25.3 18.1 28.2 27.5 

1974 Multifamily 42.4 24.8 19.0 27.8 27.5 

1975 Multifamily 42.6 25.2 19.8 27.6 27.8 

Source: U.S. Department of Commerce, Bureau of Census. 1940, 1950, and 1960 Census of Housing ; 1973-1975 Annual Housing Surveys 

Table 17..–Percentage of households living in multiunit houses 

Year Actual 

1960 23.7 

1970 27.5 

1973 26.8 

1974 26.4 

1975 26.8 

1980 

1990 

2000 

Estimates 1973 regression assuming constant model1 

1973 cooupancy rates 

24.7 

27.4 26.1 

27.9 26.8 

28.4 27.1 

28.2 27.6 

28.2 27.8 

27.5 27.5 

27.0 26.2 

1Adjusted so regression model equals actual occupancy in 1973. 

40 
Table 15..–Renter-occupied housing by type of unit and age class for 1960, 1970, and 1973 to 1975 

(Percent of all households.) 

Age class 

All House type Under 25-29 30-34 35-44 45-54 55-64 65-74 75 and house 25 over holds 

Single family 

Multifamily 

Mobile home 

Total 

Single family 

Multifamily 

Mobile home 

Total 

Single family 

Multifamily 

Mobile home 

Total 

Single family 

Multifamily 

Mobile home 

Total 

Single family 

Multifamily 

Mobilehome 

Total 

RENTERS-1960 

37.4 31.7 22.8 17.7 15.3 13.4 12.5 13.1 18.3 

39.6 29.1 20.0 16.0 16.4 18.7 18.0 17.7 19.2 

1.0 .3 .1 .1 .1 .1 .2 .2 .5 

78.0 61.1 42.9 33.8 31.8 31.2 30.7 31.0 38.0 

RENTERS-1970 

22.4 21.7 19.0 13.6 10.3 9.5 9.6 9.8 13.4 

54.4 35.8 21.9 17.0 16.0 18.7 22.1 23.3 23.2 

2.4 .9 .5 .3 .2 .2 .3 .3 .5 

79.2 58.4 41.4 30.9 26.5 28.4 32.0 33.4 37.1 

RENTERS-1973 

24.2 18.9 15.3 12.2 8.9 8.7 8.8 9.9 12.6 

51.0 36.3 23.4 15.9 13.9 14.9 19.6 23.3 22.2 

2.6 1.1 .7 .5 .4 .2 .3 .4 .6 

78.8 56.3 39.4 28.6 23.2 23.8 28.7 33.6 35.4 

RENTERS-1974 

22.2 18.6 14.5 11.8 8.3 8.9 8.2 9.7 12.0 

52.4 37.3 23.2 16.1 14.9 14.5 19.9 22.9 22.7 

3.0 1.3 .7 .5 .4 .3 .3 .5 .8 

77.6 57.2 38.4 28.4 23.6 23.7 28.4 33.1 35.5 

RENTERS-1975 

22.2 17.9 13.9 11.7 8.4 8.0 7.7 8.8 12.3 

54.8 37.9 23.1 16.3 14.1 14.6 20.1 23.7 25.6 

2.6 1.3 .9 .5 .3 .3 .3 .3 .8 

79.6 57.1 37.9 26.5 22.8 22.9 28.1 32.8 38.7 

Source:U. S. Bureau of the Census: One in1,000 Public Use Sample Tapes from 1960 and 1970 Census;Public Use Sample Tape from 1973-1975 Annual Housing 

Surveys 

39 
Table 18.-Regression coefficients for single-family housing occupancy by age class, 1976 

Family type Region Metropolitan location 

Age 

class 

Constant HH size Income 

Expenditure to 

income 

Husband 

wife Other 

family 

Primary 

individuals 

North 

east 

North South 

Central (ref) West 

In SMSA 

Central outside 

city city 

(ref) 

NonSMSA 

R2 

18-24 -0.01697 0.08370 0.14958 0.00126 – -0.02812 -0.07216 -0.11895 -0.01692 – 0.02599 -0.05902 – 0.15065 0.4236 

25-29 .04411 .09434 .15815 .00432 – -.20047 -.16018 -.16139 -.00234 – .03515 -.10059 – .06624 .6349 

30-34 .30144 .05166 .14073 .00399 – -.15710 -.33758 -.10276 .01809 – -.02927 -.14151 – .07150 .7749 

35-44 .60132 .03200 .07047 .00196 – -.13114 -.33176 -.15840 .01083 – -.01112 -.17321 – .00195 .8256 

45-54 .77674 .03082 .04024 -.00142 – -.11251 -.27741 -.11190 -.02598 – -.06169 -.13769 – .01856 .8419 

55-64 .85676 .03807 .01413 -.00420 – -.02044 -.16537 -.12712 -.00508 – -.12462 -.12846 – .04415 .8007 

65 

and 

older .84620 .06383 -.01655 -.00561 -.03498 -.11040 -.14826 -.01098 – -.18112 -.14861 – .08470 .7179 

Table 19. -Regression coefficients for apartments (two or more units) occupancy by age group, 1976 

Family type Region Metropolitan location 

Expendi- In SMSA Age Constant HH size Income ture to Husband- Other Primary North North South Central outside Non R2 

class income wife 

family 

indivi- West 

(ref) duals east Central (ref) city city SMSA 

(ref) 

18-24 0.81413 

25-29 .78197 

30-34 .54061 

35-44 .29135 

45-54 .13071 

55-64 .02186 

65 and 

older .01267 

-0.07569 -0.13588 -0.00096 – 0.11224 0.15187 0.19711 0.04537 – 0.01447 0.12572 – -0.19444 0.6712 

-.08998 -.12614 -.00318 – .22871 .19868 .21985 .05047 – .00458 .13130 – -.15011 .5830 

-.04260 -.11142 -.00302 – .17635 .38126 .12418 -.00016 – -.00085 .18151 – -.09741 .5125 

-.03002 -.05062 -.00050 – .13037 .32119 .17626 -.00207 – -.02099 .20676 – -.02980 .4432 

-.01967 -.03347 .00152 – .10354 .28130 .13468 .03630 – .02074 .17290 – -.04228 .3854 

-.02329 -.00165 .00420 – .05413 .19708 .14251 .01899 – .02532 .18741 – -.03226 .3777 

.04600 .02763 .00546 – .04682 .15549 .17376 .02105 – .02968 .24498 – -.04317 .4687 
Table 20. -Regressioncoefficients for mobile home occupancy by age class, 1976 

Family type Region Metropolitan location 

Expendi- In SMSA Age Constant HH size Income ture to Husband 

Other Primary North North South Central outside R2 

class income wife 

family indivi- east Central (ref) 

West 

city city SMSA (ref) duals (ref) 

18-24 0.20284 

25-29 .17393 

30-34 .15795 

35-44 .10733 

45-54 .09256 

55-64 .12138 

and .14113 

older 

-0.00800 -0.01371 -0.00029 – 

-.00436 -.03202 -.00114 – 

-.00906 -.02931 -.00097 – 

-.00198 -.01986 -.00146 – 

-0.08411 -0.07972 

-.02824 -.03849 

-0.07817 -0.02845 

-.05846 -.04813 

– -0.04046 -.06670 0.04380 0.1432 

– -.03974 -.03071 .08387 .1161 

– .03012 -.04000 .02591 .0774 

– .03210 -.03354 .02786 .0700 

– .04094 .03521 .02372 .0758 

– .09929 .05895 -.01190 .1165 

-.01926 -.04868 -.02142 -.01793 

.00077 -.01057 

.00897 -.00389 

-.03369 -.03171 

-.01786 -.00875 

-.02278 -.01032 

-.01539 -.01391 

-.01115 -.00677 -.00010 – 

-.01478 -.01248 .000001 – 

-.01783 -.01108 .00015 – -.01184 -.04509 -.02550 -.01007 – .15144 -.09636 -.04153 .1676 

Table 21. -Mean values of variables used in housing occupancy regression analysis by age group, 1976 

Housing type 

(proportion of 

housing units) 

Family type Metropolitan location 

(proportion of households) Region (proportion of households) (proportion of households) Expendi 

Age HH size Single Income ture to

family 

In SMSA 

income Husband Other 

wife family 

Primary 

individual 

Apart- Mobile 

ment home 

North North South Central outside NonWest housing city SMSA

units 

east Central (ref) city 

(ref)1 

No. $10,000 Pct 

18-24 2.29353 0.56739 0.09368 0.33891 0.96716 28.5445 0.53890 0.13088 0.33022 0.16272 0.28235 0.34278 0.21215 0.27377 0.42810 0.29813 

25-29 2.8211 .40737 .62038 .53057 1.35833 23.9026 .66152 .12887 .20961 .20352 .25763 .30002 .20715 .27272 .46788 .25940 

30-34 3.5296 .26679 .04159 .69166 1.60125 22.4540 .73423 .13479 .13098 .21544 .24183 .35004 .21269 .24440 .49668 .25892 

35-54 4.1209 .19628 .03117 .77255 1.78296 20.8807 .74491 .14823 .10686 .22032 .25529 .31191 .21248 .23579 .50966 .25455 

45-54 3.3756 .16456 .03596 .77953 1.8669 18.0335 .73017 .10673 .16310 .23380 .25727 .31372 .19521 .23889 .48982 .27129 

55-64 2.3967 .18480 .04331 .77186 1.5105 18.8421 .64980 .07554 .27466 .25683 .24199 .29870 .20248 .25668 .44931 .29401 

65 

and 

older 1.7344 .26851 .05623 .67526 .80056 24.9018 .43922 .07290 .48788 .23015 .26611 .31857 .18517 .27276 .38398 .34326 

1Includes small SMSA's. 

65 

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Table 24. -Elasticity of housing types relative to housing costs based upon 1970 state model and 1975 SMSA model 

Market share Average housing expenditure 

Single family Multifamily Mobile home 

SMSA MODEL 

Single family -0.54 0.07 -0.03 

Multifamily 1.15 -.08 -.08 

Mobile home -.26 -.06 .86 

Median house 

value Median rent Average depreciated 

mobile home value 

STATE MODEL 

Single family -0.40 0.03 0.18 

Multifamily 1.16 -.25 -.68 

Mobile home -.88 1.75 1.20 

1Excludes houses on more than 10 acres. 

2Excludes owned multifamily units. 

3This value is hypothetical based upon an average depreciated value derived from the age of the stock. 

Table 25. -Annual net replacement rates for conventional housing and all housing including mobile homes in the United States by regions for 1950-1956, 1960-1969, 

and 1970-1975 

U.S. Northeast North Central South West 

Period Conven- With Conven- With Conven- With Conven- With Conven- With 

mobile mobile mobile mobile mobile tional1 

homes tional homes tional homes tional 

homes tional 

homes 

Pct 

1950-1956 0.46 – 0.27 – 0.33 – 0.76 – 0.49 

1957-1959 .85 – .48 – .48 – 1.27 – 1.03 

– 

– 

1960-1969 .80 0.84 .55 0.57 .57 0.78 1.01 1.03 .92 1.02 

1970-1975 .50 .69 .24 .31 .58 .74 .88 1.12 0 .13 

1Conventional housing refers to all housing units other than mobile homes. 

Source 1950-1969–U. S. Department of Commerce Bureau of the Census U. S. Census of Housing 1960, Vol. IV. Component of Inventory Change U. S. Census of 

Housing 1970 Vol. IV. Components of Inventory Change 1973; 1970-1975 derived U. S. Bureau of Census Current Reports Series H-150 75A. Annual 

HousingSurvey, 1975, 1977. 

U S GOVERNMENT PRINTING OFFICE 1978-750126/37 44 
Appendix 

This appendix contains a list of materials 

previously sent to ORNL related to this study 

Written communications: 

October 1976 

(1) Preliminary tables on individual household regression model by age of head made 

from 1960 and 1970 Census data. 

October 1977 

(2) Analysis of housing choice report. 

November 1977 

(3) Household formation model report. 

Other materials: 

October 1977 

(1) Data deck of annual time-series variables for housing production by type of unit and 

related socioeconomic variables for 1947 to 

1976. 

(2) Computer printout of annual time-series 

regression equations to determine market 

share of housing production for single-family, 

multifamily, and mobile home housing units. 

(3) Computer printout of alternative individual regression models of housing choice based 

on 1975 annual housing survey data. 

(4) Computer printout of illustrative projections of housing-type requirements based upon 

regression equations of housing choice.