THE LONG-RANGE DEMOGRAPHIC ASSUMPTIONS

FOR THE 2015 TRUSTEES REPORT

OFFICE OF THE CHIEF ACTUARY

SOCIAL SECURITY ADMINISTRATION

July 22, 2015
Demography, Page 2

PRINCIPAL DEMOGRAPHIC ASSUMPTIONS 

OVERVIEW

SECTIONS

1 FERTILITY

2 MORTALITY

3 IMMIGRATION 
Demography, Page 3

Overview

Each year the Board of Trustees of the Federal Old-Age and Survivors Insurance (OASI) and 

Disability Insurance (DI) Trust Funds provides an annual report to the Congress on the financial 

and actuarial status of the OASDI program. The Office of the Chief Actuary (OCACT) produces 

projections of future cost and income based on three separate sets of long-range (75-year) 

assumptions for key demographic variables. The intermediate (alternative II) set of assumptions 

represents the Trustees’ best estimate for future experience, while the low cost (alternative I) and 

high cost (alternative III) sets of assumptions are more and less favorable, respectively, from the 

perspective of program cost. In addition, the intermediate assumptions serve as the central 

tendency for the stochastic projections presented in the OASDI Trustees Report. This 

memorandum presents the demographic assumptions used in the 2015 annual report of the Board 

of Trustees.

Key demographic variables are total fertility rates, average annual reductions in total age-sexadjusted mortality rates, and average annual levels of net immigration. The following table lists 

the assumed values of these key variables used in the 2015 Trustees Report. The intermediate 

ultimate total fertility rate is unchanged from the value used in the 2014 Trustees Report. 

However, the ultimate total fertility rates for the low-cost and high-cost alternatives are now 0.1 

closer to the ultimate intermediate rate than those used in the 2014 Trustees Report. The average 

annual reductions in mortality rates are essentially unchanged from those used in the 2014 

Trustees Report. The average annual net immigration is slightly higher due to the President’s 

2014 executive actions on immigration.

New data and revisions in transitioning to demographic ultimate values with fertility, mortality, 

and immigration result in a reduction (worsening) of the OASDI actuarial balance of about 0.06

percent of payroll. Other historical data updates, including updated marital status percentages,

result in an increase (improvement) of the OASDI actuarial balance of about 0.02 percent of 

payroll. In addition, revised same-sex marriage modeling results in an increase (improvement) 

of the OASDI actuarial balance of about 0.01 percent of payroll. This means that the total 

demographic changes, without factoring in recent executive actions on immigration, result in a 

reduction (worsening) of the OASDI actuarial balance of about 0.03 percent of payroll. The 

recent executive actions on immigration result in an increase (improvement) of the OASDI 

actuarial balance of about 0.02 percent of payroll when factoring in all changes, demographic 

and non-demographic.
Demography, Page 4

Key Demographic Variables for the Long-Range (75-year) Projection Period

2014 Trustees Report and 2015 Trustees Report

2014 Trustees Report 

Alternative

2015 Trustees Report 

Alternative

2015 Trustees Report Less 

2014 Trustees Report

I II III I II III I II III

Total fertility rate (children per 

woman), starting in the 25th year

2.3 2.0 1.7 2.2 2.0 1.8 -0.1 0.0 0.1

Average annual percentage 

reduction in total age-sex-adjusted 

death rates for the 75-year 

projection period

0.41 0.79 1.20 0.41 0.78 1.18 0.00 -0.01 -0.02

Average annual net legal 

immigration (in thousands, 

rounded to the nearest 5,000) for 

the 75-year projection period

1,000 790 595 1,005 795 600 5 5 5

Average annual net other-thanlegal immigration (in thousands, 

rounded to the nearest 5,000) for 

the 75-year projection period

430 335 235 455 360 250 25 25 15

The remainder of this paper provides details regarding the historical and future values for each of 

these demographic variables.
Fertility, Page 1

1. FERTILITY

ASSUMPTIONS FOR THE 2015 TRUSTEES REPORT

OFFICE OF THE CHIEF ACTUARY, SSA

TABLE OF CONTENTS PAGE

1.1 SUMMARY ................................................................................................................................. 2

1.2 HISTORICAL EXPERIENCE........................................................................................................ 2

1.3 ASSUMED FUTURE FERTILITY RATES...................................................................................... 3

TABLE 1.1: PAST AND PROJECTED TOTAL FERTILITY RATES FOR THE UNITED STATES..................................................5

TABLE 1.2: HISTORICAL TOTAL FERTILITY RATES, BY COUNTRY..................................................................................6

CHART 1.1: HISTORICAL TOTAL FERTILITY RATES FOR THE UNITED STATES ................................................................7

CHART 1.2: CENTRAL BIRTH RATES FOR FIVE YEAR AGE GROUPS: HISTORICAL AND ALTERNATIVE II PROJECTION ...8

CHART 1.3: HISTORICAL AND PROJECTED TOTAL FERTILITY RATES..............................................................................9
Fertility, Page 2

1.1 Summary

The ultimate total fertility rates (TFRs) in the 2015 Trustees Report are 2.2, 2.0, and 1.8 children 

per woman for the respective low-cost, intermediate, and high-cost alternatives. The ultimate 

TFRs used in the 2014 Trustees Report were 2.3, 2.0, and 1.7 children per woman for the 

respective low-cost, intermediate, and high-cost alternatives. Final birth data for 2012 from the 

National Center for Health Statistics (NCHS) resulted in a TFR of 1.88. The NCHS reports a 

preliminary TFR of 1.87 in 2013. 

The sharp drop in the TFR from a level of 2.12 in 2007 to a level of 2.00 for 2009 and 1.89 for 

2011 is largely due to the effects of the economic recession. Thus, for the intermediate 

alternative, the Trustees assume an increasing TFR from 2014 through 2022 to a level slightly 

above the ultimate TFR, consistent with the projected recovery from the recession. After 2022, 

the Trustees assume the TFR decreases linearly, reaching the ultimate TFR of 2.0 in 2027. 

Compared to the assumed intermediate path of the TFR in the 2014 Trustees Report, this path 

starts slightly lower and gradually approaches the 2014 Trustees Report path, reaching the postrecession peak one year later (2022), at which time the TFR for this path is slightly higher. After 

2022, this path is lower than the path in the 2014 Trustees Report because the Trustees assume 

that the ultimate TFR is reached earlier than in the 2014 Trustees Report. This change in the 

path of the TFR, along with a minor change in the path of the age-group rates reaching their 

ultimate values, results in a decrease in the long-range actuarial balance, under the intermediate 

alternative, of about 0.04 percent of taxable payroll.

In addition to the overall level of the TFR, the distribution of birth rates by age of mother has 

implications for the size of the population. As in the prior Trustees Report, the Trustees continue

the historical trend toward lower birth rates for women below age 25 and higher birth rates for 

women above age 30 through the ultimate years. This continued trend results in a somewhat 

smaller and slightly older population in the future than if the future relative distribution of birth 

rates by age of mother were unchanged. 

1.2 Historical Experience

Past total fertility rates (TFRs) in the United States are shown in table 1.1 and chart 1.1. The 

TFR for a given year is defined as the average number of children that would be born to a 

woman throughout her lifetime if she were to survive the entire childbearing period and were to 

experience, at each age of her life, the birth rate1observed in that year. During the period 1917 

through 1924, the TFR was more than 3.0 children per woman. From 1924 through 1933, the 

TFR declined from 3.1 to 2.2 children per woman, and then remained level at 2.1 to 2.2 children 

per woman through 1940. After 1940, the TFR once again began to rise, reaching a peak of 3.7 

in 1957 and stayed above 2.8 for the “baby boom” years of 1946 through 1965. This period of 

high fertility was followed by a period of declining fertility. The TFR reached a historical low of 

1.7 in 1976. Beginning in 1977, the TFR remained fairly stable at 1.8 children per woman until 

1987, when it started to increase, reaching 2.1 in 1990. Between 1990 and the start of the most 

recent recession, the TFR remained fairly stable, fluctuating between 2.0 and 2.1. The TFR 

 

1

The ratio of: (1) the number of live births to mothers of a specified age, to (2) the midyear female population of that age.
Fertility, Page 3

decreased from 2.12 in 2007 to 1.89 in 2011 and further decreased in 2012 to 1.88. Based on 

preliminary births reported in 2013, the NCHS estimates the TFR for 2013 to have been 1.87, the 

lowest TFR since 1987.

The increase in the TFR since 1976 is primarily due to increases in birth rates among women in 

their 30s. After dropping dramatically between 1960 and 1976, birth rates for women in their 

20s remained quite stable between 1976 and 2007 (see chart 1.2). Because much of the decline 

in birth rates for women in their 20s was understood to represent a desire to defer births until 

women were in their 30s, the gradual increases in birth rates for women in their 30s for 10 to 15 

years after 1976 were expected. However, birth rates for women in their 30s continued a rising 

trend through 2007, partially due to the advancement in infertility treatments.

1.3 Assumed Future Fertility Rates

The Trustees do not expect the TFR to return to the high levels experienced during the baby 

boom. Several changes in our society have occurred during the past 50 years that have 

contributed to reducing birth rates. Some of these changes are:

 increased availability and use of birth control methods,

 increased female participation in the labor force,

 increased postponement of marriage and childbearing among young women,

 increased prevalence of divorce,

 decreased death rates among children (requiring fewer births for a desired family size),

and

 increased percentage of women choosing to remain childless.

The Trustees do not expect a significant reversal of these changes. In addition, a sharp decline in 

the TFR to the low levels experienced by certain other industrialized countries is unlikely due to 

economic, demographic, and cultural differences between the U.S. and those countries. 

The Trustees assume an ultimate TFR of 2.0 for alternative II. The 2007 and 2011 Technical 

Panels both suggested keeping the ultimate alternative II TFR assumption at 2.0. In addition, in 

their latest projection published in 2014, the Congressional Budget Office assumed an ultimate 

TFR assumption of 2.0.2 The 2014 National Population Projections released by Census have a 

slightly lower TFR path. In those projections, Census assumptions result in a TFR in 2014 of 

1.87. Then, Census’ TFR stays almost constant throughout their projection through 2060.3

As shown in chart 1.2, there is a continuation of the historical trend for, generally, increasing 

birth rates for women over age 30 and decreasing rates for women below age 25 through the 

ultimate year, with age-specific rates remaining constant thereafter. This changing distribution 

of fertility rates by age of woman has significant effects on population size, but these effects 

essentially stabilize once the age distribution of fertility rates stabilizes. 

Examining data from other countries is useful in selecting a range of ultimate assumptions for 

the low-cost and high-cost alternatives. Historical TFRs during the period 1980-2011 that were 

 

2

See http://www.cbo.gov/sites/default/files/45471-Long-TermBudgetOutlook_7-29.pdf

3

See http://www.census.gov/population/projections/files/methodology/methodstatement14.pdf
Fertility, Page 4

reported to the United Nations are shown for 24 nations in table 1.2. The TFRs for the most 

recent year shown in the table range from 2.5 in India to 1.4 in Austria, Germany, Greece, Italy, 

Japan, Portugal, and Spain. However, if India is excluded from the comparison, the highest TFR 

is 2.1 for Mexico and New Zealand followed by 2.0 for France and Ireland. Although the TFR 

in the industrialized countries has been observed at levels as low as the 1.2 to 1.5 range, the 

cultural and economic climate in the U.S. makes it highly unlikely that our TFR will go to the 

level of 1.7 achieved in 1976 for any sustained period. Thus, the Trustees assume an ultimate 

TFR for the high-cost scenario of 1.8 children per woman. Using the range of past experience 

for the United States and other nations as a guide, the Trustees assume an ultimate TFR for the 

low-cost scenario of 2.2 children per woman.

For the intermediate alternative, the Trustees assume the ultimate TFR is reached in the 5

th year 

from the post-recession peak TFR year of 2022. For the low-cost alternative, the Trustees 

assume the ultimate TFR is reached in 2023 and for the high-cost alternative, the Trustees 

assume the ultimate TFR is reached in 2032. In prior Trustees Reports, the ultimate TFRs were

reached in the 25th year of the projection period.

For the intermediate assumptions, the Trustees assume the TFR:

 Increases over the period from 2014 through 2022, consistent with the economic 

recovery;

 Reaches 2.065 in 2022, which is approximately the average TFR from 2000 to the 

beginning of the most recent recession; and

 Decreases linearly after 2022, reaching the ultimate TFR of 2.0 in 2027.

For the low-cost and high-cost alternatives, the Trustees assume the paths of the TFRs gradually 

grade away from the intermediate alternative path until 2022 and then linearly grade to the

ultimate TFRs in 2023 and 2032, respectively. Chart 1.3 shows the historical path of the TFR 

starting in 1980 and the projected paths of the TFRs for all three alternatives.
Fertility, Page 5

Table 1.1: Past and Projected Total Fertility Rates for the United States

Calendar Year 2015 Trustees Report 2014 Trustees Report

1920 3.263 3.263

1930 2.533 2.533

1940 2.229 2.229

1950 3.028 3.028

1960 3.606 3.606

1965 2.882 2.882

1970 2.432 2.432

1975 1.770 1.770

1980 1.820 1.820

1985 1.835 1.835

1990 2.069 2.069

1991 2.057 2.057

1992 2.043 2.043

1993 2.018 2.018

1994 2.002 2.002

1995 1.981 1.981

1996 1.980 1.980

1997 1.974 1.974

1998 2.002 2.002

1999 2.008 2.008

2000 2.054 2.054

2001 2.032 2.032

2002 2.025 2.025

2003 2.055 2.055

2004 2.059 2.059

2005 2.062 2.062

2006 2.112 2.112

2007 2.123 2.123

2008 2.074 2.074

2009 2.002 2.002

2010 1.926 1.926

2011 1.891 1.892

2012 1.877 1.881 1

2013 1.870 1 1.894 2

2014 1.884 2 1.913 2

Alternative I:

2015 1.921 1.961

2020 2.128 2.139

2025 2.200 2.194

2030 2.200 2.235

2035 2.200 2.275

2039 + 2.200 2.300

Alternative II:

2015 1.906 1.937

2020 2.036 2.055

2025 2.026 2.050

2030 2.000 2.031

2035 2.000 2.011

2039 + 2.000 2.000

Alternative III:

2015 1.890 1.913

2020 1.943 1.971

2025 1.899 1.906

2030 1.828 1.827

2035 1.800 1.747

2039 + 1.800 1.700

1

 Preliminary Social Security Administration

2

 Estimated Office of the Chief Actuary

July 22, 2015
Fertility, Page 6

Table 1.2: Historical Total Fertility Rates, by Country

1980 - 2011

Country 1980 1985 1990 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 Most Recent TFR

Australia 1.9 1.9 1.9 1.7 1.8 1.7 1.8 1.8 1.8 1.9 2.0 1.9 1.9 1.9 1.9

Austria 1.7 1.5 1.5 1.3 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.4

Belgium 1.7 1.6 1.6 — — — — — — 1.8 — — 1.8 1.8 1.8

Canada 1.7 1.6 1.8 1.5 1.5 1.5 1.5 1.5 1.6 1.7 1.7 1.7 — — 1.7

China 2.2 2.2 2.3 — — — — — — — — — — — 1.8

Denmark 1.5 1.4 1.7 1.7 1.7 1.8 1.8 1.8 1.9 1.8 1.9 1.8 1.9 1.8 1.8

Finland 1.6 1.6 1.8 1.7 1.7 1.8 1.8 1.8 1.8 1.8 1.8 1.9 1.9 1.8 1.8

France 2.0 1.8 1.8 1.9 1.9 1.9 1.9 1.9 2.0 2.0 2.0 — 2.0 2.0 2.0

Germany 1.5 1.4 1.3 1.3 1.3 1.3 1.4 1.3 1.3 1.4 1.4 — 1.4 1.4 1.4

Greece 2.2 1.5 1.4 1.3 1.3 1.3 1.3 1.3 1.4 1.4 1.5 1.5 — 1.4 1.4

India 4.4 4.3 3.8 3.1 3.0 3.0 2.9 2.9 2.8 2.7 2.6 2.6 2.5 — 2.5

Ireland 3.2 2.5 2.2 2.0 2.0 2.0 2.0 1.9 1.9 2.0 2.1 2.0 2.1 2.0 2.0

Italy 1.6 1.4 1.4 1.3 1.3 1.3 1.3 1.3 1.4 1.4 1.4 1.4 1.4 1.4 1.4

Japan 1.7 1.7 1.5 1.3 1.3 1.3 1.3 1.3 1.3 1.3 1.4 1.4 1.4 1.4 1.4

Mexico 1 3.1 3.3 3.7 2.5 2.3 2.3 2.2 2.2 2.2 2.1 2.1 — — — 2.1

Netherlands 1.6 1.5 1.6 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.8 1.8 1.8 1.8 1.8

New Zealand 2.0 1.9 2.2 2.0 1.9 1.9 2.0 2.0 2.0 2.2 2.2 2.1 2.1 2.1 2.1

Norway 1.7 1.7 1.9 1.8 1.8 1.8 1.8 1.8 1.9 1.9 2.0 2.0 2.0 1.9 1.9

Portugal 2.1 1.7 1.5 1.5 1.5 1.4 1.4 1.4 1.4 1.3 1.4 1.3 — 1.4 1.4

Spain 1.9 1.6 1.3 1.2 1.3 1.3 1.3 1.3 1.4 1.4 1.5 1.4 1.4 1.4 1.4

Sweden 1.7 1.7 2.1 1.6 1.7 1.7 1.8 1.8 1.9 1.9 1.9 1.9 2.0 1.9 1.9

Switzerland 1.5 1.5 1.6 1.4 1.4 1.4 1.4 1.4 1.4 1.5 1.5 1.5 1.5 — 1.5

United Kingdom 1.8 1.8 1.8 1.6 1.6 1.7 1.8 1.8 1.8 1.9 2.0 — — 1.9 1.9

United States 2

1.8 1.8 2.1 2.0 2.0 2.0 2.1 2.1 2.1 2.1 2.1 2.0 1.9 1.9 1.9

1

 Estimate for Mexico (from INEGI website) for 1999 -- 2.9

2

 Estimate for the U.S. from NCHS NVSR 62-09

Source: United Nations Demographic Yearbook Historical Supplement 1948-1997

 United Nations Demographic Yearbook Fertility Supplement 1980-1999

 United Nations Demographic Yearbooks 2000 - 2011

Social Security Administration

Office of the Chief Actuary

July 22, 2015
Fertility, Page 7

Chart 1.1: Historical Total Fertility Rates for the United States

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 Total Fertility Rate

Calendar Year

Social Security Administration

Office of the Chief Actuary

July 22, 2015
Fertility, Page 8

Chart 1.2: Central Birth Rates for Five Year Age Groups: Historical and Alternative II Projection

0.00

0.05

0.10

0.15

0.20

0.25

0.30

1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030 2035 Central Birth Rate

Calendar Year

Historical Alternative II

Projection

14-19

25-29

20-24 30-34

40-44

35-39

45-49

Social Security Administration

Office of the Chief Actuary

July 22, 2015
Fertility, Page 9

Chart 1.3: Historical and Projected Total Fertility Rates

1.7

1.8

1.9

2.0

2.1

2.2

2.3

1980 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030 2035 2040 Total Fertility Rate

Calendar Year

Historical

Alternative I

Alternative II

Alternative III

Social Security Administration

Office of the Chief Actuary

July 22, 2015
Mortality, Page 1

2. MORTALITY

ASSUMPTIONS FOR THE 2015 TRUSTEES REPORT

OFFICE OF THE CHIEF ACTUARY, SSA

TABLE OF CONTENTS PAGE

2.1 SUMMARY ................................................................................................................................. 2

2.2 CONSIDERATIONS IN SELECTING MORTALITY ASSUMPTIONS ............................................... 2

2.3 TRUSTEES’ ASSUMPTIONS VERSUS HISTORICAL TRENDS AND OTHER ASSUMPTIONS .......... 4

2.4 PAST EXPERIENCE BY CAUSE OF DEATH................................................................................. 7

2.5 RECOMMENDATIONS OF THE PREVIOUS TECHNICAL PANELS AND OTHER PROJECTIONS ... 7

2.6 ASSUMED FUTURE RATES OF REDUCTION .............................................................................. 8

TABLE 2.1: HISTORICAL AND ASSUMED RATES OF REDUCTION IN MORTALITY...........................................................11

TABLE 2.2: AVERAGE ANNUAL PERCENT REDUCTIONS IN AGE-ADJUSTED CENTRAL DEATH RATES: FOR THE 

2015 TRUSTEES REPORT .......................................................................................................................................14

TABLE 2.3: AVERAGE ANNUAL RATES OF REDUCTION IN CENTRAL DEATH RATES BY AGE GROUP, SEX, AND 

CAUSE...................................................................................................................................................................16

TABLE 2.4: AGE-SEX-ADJUSTED CENTRAL DEATH RATES ..........................................................................................17

CHART 2.1: HISTORICAL UNITED STATES AGE-SEX-ADJUSTED CENTRAL DEATH RATES FROM 1900-2011................18

CHART 2.2: DIFFERENCE BETWEEN MALE AND FEMALE ANNUAL PERCENT REDUCTION IN AGE-ADJUSTED 

DEATH RATES FOR POPULATION 65+....................................................................................................................19
Mortality, Page 2

2.1 Summary 

For the 2015 Trustees Report, the assumed ultimate annual rates of mortality reduction by age 

and cause of death remain the same as those used in the 2014 Trustees Report. The assumed 

ultimate rates of reduction apply for years after 2038 in the projection.

Under the intermediate assumptions, projected age-sex-adjusted death rates are, in general, 

slightly higher than the death rates in last year’s report due to the addition of final data for 2011 

and preliminary Medicare data for 2012. By age group, these additional data result in lower 

projected death rates for the age group under 65 and higher projected death rates for the age 

group 65 and over. This results in an increase (improvement) in the long-range actuarial balance, 

under the intermediate set of assumptions, of about 0.02 percent of taxable payroll. 

The low-cost and high-cost alternatives are a percent of the intermediate alternative and, as such, 

are not displayed separately in the tables. Male and female ultimate rates of improvement have 

been set equal to each other, but are displayed separately for comparing to historical values.

2.2 Considerations in Selecting Mortality Assumptions

Projections of mortality improvement are subject to uncertainty that is possibly greater than any 

other variable used in Trustees’ assumptions. Some demographers argue that life expectancy is 

potentially limitless and that rates of mortality reduction will increase substantially in the future. 

Others believe that mortality improvement will be substantially more difficult to achieve in the 

future, and that rates of reduction will diminish rapidly.

Lee and Carter have suggested that, in the face of such uncertainty, a prudent choice for future 

rates of mortality improvement might be to assume a continuation of the average trends 

experienced over a long historical period. Key to this approach is the selection of the 

“appropriate” historical period to be used in determining the annual projected levels of mortality 

reduction. For many years, Lee and Carter suggested using the period starting with 1900. The 

average rate of mortality improvement for the group aged 65 and older during this period (0.78 

percent) is close to the average rate for the intermediate assumptions during the 2011-89 period 

(0.71 percent). More recently, Lee and Carter have suggested a period about half as long, 

starting with 1950, which would result in somewhat faster projected rates of mortality 

improvement. If a period twice as long were to be used (1800-2000), then the rates of reduction 

would be substantially less. Relative to the entire period of existence of humankind, the 

twentieth century was a time of exceptionally rapid mortality decline.

Using extrapolation of the average trends experienced for the past century (or for any other 

period) to project future mortality presumes that there will be constancy to these rates of change 

in the future that has not occurred in the past. We believe it is crucial to study not only the 

differing historical rates of decline for various periods, but also the conditions that contributed to 

these variations. Only after considering how future conditions will differ from the past can we 

speculate about future mortality improvement.
Mortality, Page 3

A number of extremely important developments have contributed to the generally rapid overall 

rate of mortality improvement during the past century. These developments include:

• Access to primary medical care for the general population (in particular, the access due 

to Medicare and Medicaid health coverage for the elderly, disabled, and poor),

• Discovery of and general availability of antibiotics and immunizations, 

• Clean water supply and waste removal, and 

• The rapid rate of growth in the general standard of living. 

Each of these developments is expected to make a substantially smaller contribution to annual 

rates of mortality improvement in the future. 

Future reductions in mortality will depend upon such factors as: 

• The development and application of new diagnostic, surgical, and life-sustaining 

techniques,

• The rate of future increase in health spending and the efficiency of that spending relative 

to mortality improvement,

• The presence of environmental pollutants, 

• Changes in amount and type of physical activity, 

• Improvements in nutrition, 

• The incidence of violence and suicide, 

• The isolation and treatment of causes of disease, 

• The emergence of new forms of disease, 

• The evolution of existing forms of disease, 

• Improvements in prenatal care, 

• The prevalence of obesity,

• The prevalence of cigarette smoking, 

• The misuse of drugs (including alcohol), 

• The extent to which people assume responsibility for their own health, 

• Education regarding health, and 

• Changes in our perception of the value of life. 

In reviewing the above list, future progress for some factors seems questionable when recent 

statistics are considered. Recent National Center for Health Statistics (NCHS) releases have 

reported a substantial increase in the prevalence of obesity and diabetes, decreased 

environmental air quality, and an increase in negative side effects from invasive surgical 

procedures. On the other hand, there is good basis for speculation that there will be substantial 

breakthroughs in advancing medical technology and treatment in the future. The extent to which 

such new technologies will have purely positive effects (like improved sanitation) versus mixed 

effects (as in the case of chemotherapy) will determine their potential for improving mortality. A 

fundamental consideration, however, is the ability and willingness of our society to pay for the 

development of new treatments and technologies, and to provide these to the population as a 

whole. 

Can we expect future economic growth to continue to have as much impact on medical advances 

and mortality improvement as it had during 1900-2011? For the intermediate assumptions, 

economic projections for productivity and real wage growth are similar to the historical 
Mortality, Page 4

experience during 1900-2011. However, the rate of future increases in medical spending as a 

percent of GDP is assumed to be slower than in recent decades. Thus, a slower real rate of 

increase in medical spending projected for the future would be consistent with assuming that the 

rate of future improvement in mortality will be somewhat lower than the average rate during 

1900-2011. 

Education and income are factors that are well correlated with mortality differences in the 

population. More education and higher income are associated with lower mortality. It is not 

entirely clear whether this correlation is largely due to the benefits of higher income and 

education, or to the “selection” of more advantaged (and thus healthier) individuals in gaining 

access to the best education and job opportunities. If the former factor is important, then 

increasing education and income for the population as a whole may provide some further 

benefits, but substantially less than in the past. 

Future progress in treatment of currently predominant diseases is contingent on the availability 

of funding, research outcomes, society’s views on moral issues, and education about lifestyle 

choices that affect one’s health. Quality of life and years of healthy living are improving on a 

continual basis. Once fatal diseases are being controlled or cured. Education and awareness of 

healthy living allows persons to continue enjoying low morbidity far longer than previous 

generations. As this trend continues, the rates of mortality improvement for older ages will 

gradually approach the rates of improvements for younger ages. Future medical breakthroughs 

will cause today’s predominant causes of death to become less dominant through continued 

research and education. This rapid reduction of today’s most common causes of death will result 

in other causes, which have slower rates of improvement or have not yet emerged, becoming the 

predominant causes. Due to this, many causes of death that have recently had rapid rates of 

reduction will have slower rates in the future. Similarly, causes that have recently had slower 

rates of improvement will likely have more rapid rates in the future.

Finally, we must consider that improvements in mortality and extension of longevity through the 

last century were relatively unconstrained by limitations of senescence and gradual deterioration 

of body systems. While we do not subscribe to the notion that there is a fixed limit for human 

longevity, it is true that average human lifespan has improved more than the maximum observed 

lifespan. This suggests that even with continued technological advances, the inherent limitations 

of the physical body and the mind to endure successfully past 110 years will gradually result in a 

decelerating force of mortality improvement. This maximum observed lifespan can be expected 

to continue increasing, but only at a very modest pace.

2.3 Trustees’ Assumptions versus Historical Trends and Other Assumptions 

Table 2.1 shows average rates of reduction in mortality for three broad age groups over two 

historical periods. In addition, the table includes the following ultimate rates of reductions (the 

rate of reduction in mortality averaged over the last 50 years of the 75-year long-range period): 

 Those assumed for the intermediate ultimate assumptions for various Trustees reports 

(choosing those reports that included changes in the ultimate assumptions or in the 

methodology), 

 Those recommended by various Technical Panels, and 
Mortality, Page 5

 Those resulting from a survey taken at a Society of Actuaries (SOA) seminar. 

Rates of improvement shown on the first page of table 2.1 reflect age-sex adjustment to the 

distribution of the 1990 U.S. population; those on the second page use the distribution of the 

2000 U.S. population; and those on the third page use the distribution of the 2010 U.S. 

population. As seen by comparing the rates on the first and second pages in table 2.1 under the 

intermediate assumptions of the 2002 and the 2004 Trustees Reports (for which ultimate rates of 

improvement were the same), the difference in using the different populations for age-sex 

adjusting makes little difference in the ultimate average rates by the broad age groups. This 

conclusion is further supported by comparing the rates from the 2013 Trustees Report using two 

different populations for age-sex adjusting, as shown on the second and third pages in table 2.1. 

For presentations other than table 2.1 of this memorandum, rates of improvement are presented 

with age-sex adjustment to the distribution of the 2010 U.S. population.

Table 2.1 provides the assumed ultimate average annual percent reductions in mortality for the 

intermediate assumptions of the 1999, 2000, 2002, 2004, 2008, 2009, 2011, 2013, 2014 and 2015 

Trustees Reports. The 1999 and 2000 Trustees Reports are included because ultimate annual 

percent reductions were increased substantially in the 2000 Trustees Report. The 2002 Trustees 

Report is included because changes in methodology were made that resulted in increased 

ultimate annual percent reductions. The 2004 Trustees Report is included to provide 

comparability in the results using a different population for the purpose of age-sex adjustment. 

The 2008 and 2009 Trustees Reports are included because ultimate annual percent reductions 

were revised. The 2011 Trustees Report is included because changes in methodology were made 

that put more emphasis on the recent historical data. The 2013 Trustees Report values are shown 

on both the second and third pages of the table to compare results using different populations for 

age-sex adjustment. For comparison purposes, we include the values from the prior and current

Trustees Reports.

Also included in table 2.1 are the assumed ultimate annual percent reductions in mortality 

recommended by the 1994-96, 1999, 2003, 2007, and 2011 Technical Panels and the median 

response from actuaries, demographers, biologists, and economists who participated in the 1997 

Society of Actuaries Seminar. Focusing on mortality for ages 65 and over, it should be noted 

that since 2000, the Trustees’ intermediate assumptions have provided for an ultimate rate of 

reduction that is somewhat less than the average experienced since 1900. While the 1999 

Technical Panel recommended significantly faster ultimate rates of reduction, the 2003 Panel 

suggested rates of reduction closer to the Trustees’ assumptions. In addition, the improvement 

suggested by the 2003 Panel would be even closer to the Trustees’ assumptions if the 

deceleration they envisioned were assumed to occur more uniformly in the future, rather than 

just starting after 75 years. The 2007 Technical Panel recommended faster improvement than 

what has been assumed by the Trustees and recommended using the experience since 1950 as the 

primary basis for setting the rates of improvement. The 2011 Technical Panel recommended 

targeting 88.7 years of life expectancy at birth in 2085, which implied a considerably faster 

ultimate rate of improvement. A further analysis of the recommendations of previous technical 

panels is presented later in this report. 
Mortality, Page 6

Comparisons of historical and assumed rates of improvement are included in table 2.2. All rates 

of improvement shown in this table reflect age-sex adjustment1to the distribution of the 2010 

United States population. For the age group 65 and over (where mortality is concentrated), the 

rate of improvement experienced during 1900-2011 averaged 0.78 percent, while the rate of 

improvement during 1982-2011 averaged 0.82 percent. Thus, the average rate of improvement 

for the most recent 29 years about equaled the average rate of improvement for the entire 1900-

2011 period. In fact, mortality at ages 65 and over generally improved at about this rate, or less, 

during 1900-2011 with the exception of two notable periods. The first was for the World War II 

period and subsequent years, 1936-1954. During this time frame, dramatic advances in the 

standard of living were achieved due to expanded medical practice including the introduction of 

antibiotics. The second period was from 1968-1982, during which additional dramatic 

advancements in medicine were made and access to medical services was greatly expanded 

through Medicare and Medicaid for the old, frail, and disadvantaged, those who account for the 

vast majority of deaths in the population.

Chart 2.1 displays the annual age-sex-adjusted central death rates experienced since 1900. An 

examination of these rates reveals a sequence of distinct periods of mortality reduction. Table 

2.2 provides average annual rates of reduction2for these periods. During the period 1900-1936, 

annual mortality reduction averaged about 0.7 percent for males and 0.8 percent for females. 

During the following period, 1936-1954, there was more rapid reduction (with the help of 

antibiotics and other medical advances), averaging 1.5 percent per year for males and 2.3 percent 

per year for females. The period 1954-1968 saw a much slower reduction of 0.7 percent per year 

for females and an increase of 0.3 percent per year for males. From 1968 through 1982, rapid 

reduction in mortality surged (with the help of Medicare and Medicaid), averaging 1.8 percent 

for males and 2.1 percent for females, annually. From 1982 to 2011, more moderate reduction in 

mortality returned, averaging 1.3 percent per year for males and 0.6 percent for females.

For the period 1982-2011, the average annual rate of improvement for females was considerably 

less than that for males. For all other periods mentioned above, the opposite is true, i.e., the 

average annual rate of improvement for males is less than that for females. Chart 2.2 shows 

differences between male and female annual rates of mortality improvement for the age group 65 

and older for each year of the period 1969 through 2012. (Note that although the last year of 

NCHS mortality data, which is disaggregated by cause of death, is 2011, the Medicare data is 

available through 2012.) Differences are shown for rates based on Medicare data. Even with 

normal year-to-year variation, improvement was generally greater for females until about 1980, 

as had been the case since the beginning of the past century. However, female improvement was 

generally less than or equal to that for males beginning about 1980.

 

1

 The age-sex-adjusted death rate is the crude rate that would occur in the enumerated total population as of April 1, 

2010, if that population were to experience the death rates by age and sex observed in, or assumed for, the selected 

year.

2 Average annual reductions were calculated as the complement of the exponential of the slope of the least-square 

line through the logarithms of the central death rates. The rates for the period 1900-2011 are a weighted average of 

the rates shown for the five separate distinct periods of change.
Mortality, Page 7

2.4 Past Experience by Cause of Death

In the past, the reduction of mortality rates has varied greatly by cause of death. In assessing

experience and future possible improvement in mortality, we believe it is useful to understand 

the variations in mortality by cause of death. For the period 1979-2011, we analyzed average 

annual reductions in central death rates by age group and sex for four major groups of causes of 

death, and a residual group (Other) that contains all other causes (see table 2.3). For all ages

combined, the largest rate of reduction was in the category of Cardiovascular Disease, which has

been about 2.6 percent for males and about 2.3 percent for females. The rate of reduction for 

Cancer has been about 0.9 percent per year for males and about 0.4 percent per year for females. 

The category of Violence, which includes accidents, averaged about 0.7 percent reduction for 

males, but an increase in mortality of about 0.2 percent for females. The Respiratory Diseases 

category averaged about 0.2 percent reduction for males and about 1.8 percent increase for 

females. The Other Causes category averaged increases in mortality of about 0.9 and 1.6 percent 

per year for males and females, respectively. 

2.5 Recommendations of the Previous Technical Panels and Other Projections

The 2011 Technical Panel appointed by the Advisory Board recommended an increase in life 

expectancy at birth that was consistent with generally larger rates of mortality reduction than 

those assumed under the 2011 Trustees Report. Their recommendation was for reductions in 

mortality that would result in a life expectancy at birth of 88.7 in 2085. This is consistent with 

having an annual 1.26 percent reduction in death rates for all ages and both sexes. This is a large 

increase over the recommendation of the 2007 Technical Panel.

The 2007 Technical Panel appointed by the Advisory Board recommended generally larger rates 

of decline than those assumed under the 2007 Trustees Report. Their recommendation was for 

an assumption of 1.0 percent annual reduction in death rates for all ages and both sexes. Their 

recommendation was based on the average rate of reduction in the total population (all ages 

combined) observed for the period 1953-2003.

We feel that the approach of the 2007 and 2011 Technical Panels fails to take into account 

significant deviations in the rates of reduction by age groups as evidenced by the data shown in 

tables 2.2 and 2.3. The rates of reduction at younger ages have been much larger than the rates 

experienced at older ages. While we agree that differences by age will diminish in the future, we 

do not believe they will vanish. 

The 2007 and 2011 Technical Panels’ recommendations stand in stark contrast to that of the 

2003 Technical Panel, which recommended using the rates of reduction by age and year as 

indicated in the table below. For rates of reduction for years between 2002 and 2012, the given 

rates of reduction are interpolated between these two years. Similarly, for each year, agespecific rates are interpolated between the ages given in the table. The 2003 Technical Panel 

also recommended that there be no differentiation between males and females.
Mortality, Page 8

2003 Technical Panel Assumed Ranges of Mortality Decline By Age

Exact Age Initial 2000-2002 Ultimate 2012-2077

0 2.84 2.50

20 1.16 1.11

75 1.16 1.11

95 -0.48 0.64

122.5 -0.48 0.00

A key finding of the 2003 Technical Panel was their recognition of the likelihood that mortality 

improvement will decelerate in the future. This general concept is entirely consistent with the 

assumptions used in the Trustees Reports for decades. However, the panel’s approach was 

somewhat awkward. While they assumed deceleration for ages up to about 80 through 2012, 

they assumed no deceleration between 2012 and 2077. After 2077 though, the 2003 Panel 

assumed all rates of decline would decelerate to the point of having no further decline in 

mortality after around 2200. We believe that the Trustees’ assumptions present a superior 

approach compared to the approach recommended by the 2003 Technical Panel. Through the 

use of different death rates by cause, the Trustees’ assumptions resulted in a steady deceleration 

at a very slow pace, which continued throughout the 75-year period and indefinitely thereafter,

and approached rates of decline that are about one-third the rates assumed for the earlier portion 

of the projection period (rather than reaching zero decline by 2200).

The Congressional Budget Office assumed mortality rates will decrease by 1.17 percent per year 

for all ages and both sexes in their 2014 publication. This results in a life expectancy at birth of 

85.2 years in 2060.3 Comparing with Census, the assumed mortality rates in the 2014 National 

Population Projections result in a life expectancy at birth of 85.6 in 2060.4

2.6 Assumed Future Rates of Reduction

Table 2.4 provides age-sex-adjusted mortality rates for historical years and the assumed future 

rates of reduction. For the 2015 Trustees Report, the base year for the mortality projections is 

2011. However, this report also includes an additional year of Medicare data for ages 65 and 

older. The age-sex-adjusted mortality rates presented in table 2.4 use the 2010 Census resident 

population as the standard population for the age-sex adjustment. 

Instead of using the measured mortality rates for the last single year of data (calendar year 2011) 

as the starting point of the mortality projections, we use a set of mortality rates calculated to be 

consistent with the trend inherent in the last 12 years of available data. The last 12 years of data 

are 2000-2011 for ages under 65, and 2001-2012 for ages 65 and older. This approach reduces 

the impact of wide fluctuations that tend to occur in annual data on the starting levels used for 

the mortality projection. 

Because reductions in mortality have differed widely by age in the past, the ultimate reductions 

in death rates vary by age group. Historically, reductions have been very rapid at the youngest 

 

3

See http://www.cbo.gov/sites/default/files/45471-Long-TermBudgetOutlook_7-29.pdf

4

See Table 17 at http://www.census.gov/population/projections/data/national/2014/summarytables.html
Mortality, Page 9

ages. However, reductions at the highest ages, ages 85 and over, have been very slow. The 

Trustees’ assumptions have reflected for many years the belief that neither of these extremes will 

persist indefinitely into the future. The Trustees’ assumptions have reflected slower 

improvement at the youngest ages than evidenced since 1900 and faster improvement at the 

highest ages (85 and over) than experienced historically. While this “compression” of rates of 

mortality improvement is in conflict with a literal interpretation of the Lee and Carter method, it 

was nevertheless endorsed explicitly by the 1999 Technical Panel, where Ron Lee was the 

principal demographer on the panel.

Assumed rates of improvement in mortality by cause of death have long played a role in the 

projection of ultimate mortality improvement for the Trustees Reports. These rates of 

improvement by cause of death (see table 2.3) serve as an important basis for analysis relative to 

past trends and for an initial assessment of potential future mortality improvement. Rates of 

improvement by cause provide a useful, even if sometimes indirect, basis for analysis of past 

effects for specific behavioral and health trends, like the evolution of heart disease and cancer 

over time. Data specific to behavioral aspects like diet, exercise, stress, and smoking, for 

example, are not directly applicable death rate trends. Trends in death rates by cause serve as 

proxy for linking these behaviors to death rates. 

The averaging period for determining starting levels of annual mortality reduction is 10 years. 

Average annual reductions observed for the period 2001-2011 for ages under 65 are calculated 

by age group, sex, and cause. For ages 65 and older, an additional year of Medicare data is 

included (with the 2012 Medicare deaths allocated by cause of death using the 2011 NCHS 

proportions); the average annual reduction in the period 2002-2012 determines the starting level. 

These starting levels of annual reductions are used to estimate death rates for preliminary years –

i.e., years between the year of final data (2011 for ages under 65, and 2012 for ages 65 and older) 

and the year of the Trustees Report (2015). For years after 2014, the reductions in mortality 

under Alternative II are assumed to change rapidly from the starting levels5of average annual

reductions to the assumed ultimate rates of reduction for years 2039 and later. Under the lowcost and high-cost scenarios, the starting levels of average annual reduction are assumed to be 50 

percent and 150 percent,6respectively, of the starting levels for Alternative II.

For the 2015 Trustees Report, the ultimate rates of improvement in the low-cost and high-cost 

scenarios are a ratio of the intermediate alternative, with low-cost being 1/2 of the intermediate 

rates of improvement and the high-cost being 5/3 of the intermediate rates. The ultimate average 

annual percentage reductions by age group and cause of death for the intermediate alternative of 

the 2015 Trustees Report are presented in table 2.3, along with the intermediate assumptions 

from the 2014 Trustees Report, and the average rates experienced during the period 1979-2011

and 2001-2011. 

 

5

If the starting level of annual reductions for a particular cause age-sex group is negative, then 75 percent of that 

starting level is assumed for the intermediate alternative.

6

If the starting level of annual reductions for a particular cause age-sex group is negative, then 100 percent of that 

starting level is assumed for the low-cost alternative and 50 percent is assumed for the high-cost alternative.
Mortality, Page 10

Table 2.2 shows historical rates of improvement and the rates of improvement by alternative for 

the 2015 Trustees Report, summarized by age group and sex. For the intermediate alternative, 

projected rates of improvement for ages under 50 are generally lower than those experienced 

over the period 1900-2011, consistent with our expectation of continued generally slower 

improvement in the future for these age groups. For males age 50 and older, the average 

projected rates of improvement for years after 2011 are slightly higher than those experienced 

since 1900. The projected rates of improvement for women age 50 and older are slightly lower 

than those assumed for men and generally lower than the rates experienced by this group of 

women over the period 1900-2011. This is consistent with our long-held belief that average rates 

of mortality improvement for women, which had been faster than for men until around 1980, 

would ultimately converge with male improvement rates. Evidence that improvement for 

females will not always be faster than for males is apparent in data for years since 1980. The 

rate of improvement in mortality for women age 65 and older averaged only 0.45 percent per 

year during the period 1982-2011. This amount was a little more than one-third the average rate 

of improvement for aged men during this period (1.13 percent). 

Table 2.2 also shows that, for all ages combined, the rate of improvement under the intermediate 

alternative for the period 2039-2089 is 0.73 percent per year for men and 0.68 percent per year 

for women. The ultimate rates of improvement in the 2014 Trustees Report were 0.74 and 0.69

percent per year for males and females, respectively.

A comparison of the basis for past improvement in mortality with the expected basis for future 

improvement suggests that future improvement is likely to continue, but at a generally slower 

rate than experienced during the extraordinary 1900-2011 period for ages under 65. It seems 

more reasonable to expect the rate of mortality improvement for the age group 65 and older for 

the next 75 years to be close to that experienced during 1900-2011 (0.78 percent as shown in 

table 2.2). The trustees believe the average annual rate of decline of 0.71 percent (as shown in 

table 2.2) over the period 2011-2089 for the intermediate assumption is reasonable in this 

context.
Mortality, Page 11

Table 2.1: Historical and Assumed Rates of Reduction in Mortality1

1999 1994-96 October-97 1999 2000 2002 2003

1900-2000 1982-2000

Trustees 

Alternative 22

Technical 

Panel3

SOA 

Seminar4

Technical 

Panel5

Trustees 

Alternative 26

Trustees 

Alternative 27

 Technical 

Panel8

0 - 14 3.30 2.74 1.20 3.30 0.95 2.20 1.35 1.55 2.33

15 - 64 1.44 1.15 0.57 1.40 0.75 1.12 0.75 0.78 1.11

65 & Over 0.73 0.49 0.50 0.75 0.60 0.98 0.65 0.70 0.92

1Rates of reduction are the average of male and female annual rates of decline in age-adjusted central death rates. The rates for the period 1900-2000 are a weighted

 average of rates for five separate distinct periods of change.

2The 1999 Trustees ultimate intermediate assumptions are for the period 2023-2073.

3The 1994-96 Technical Panel (appointed by the Advisory Council) recommended assuming reduction at the average rate experienced during the century.

4The Society of Actuaries Seminar included 60 actuaries, demographers, economists, and other experts on Social Security financing. 

 Values shown are the median responses of the participants.

5The 1999 Technical Panel (appointed by the Advisory Board) recommended that ultimate rate of reduction in mortality be increased at all ages

 (over the 1999 TR assumptions) by enough to increase the projected life expectancy at birth for 2070 by 3.7 years (to the level assumed for the high-cost alternative).

6The 2000 Trustees ultimate intermediate assumptions are for the period 2024-2074. Ultimate rates of mortality reduction increased.

7The 2002 Trustees ultimate intermediate assumptions are for the period 2026-2076. Changes to projection methodology increased rates of mortality reduction.

8The 2003 Technical Panel ultimate assumptions are for the period 2027-2077.

Social Security Administration

Office of the Chief Actuary

July 22, 2015

Assumed ultimate annual percent reductions in age-sex-adjusted death rates

Historical average 

annual percent 

reductions in 

age-sex-adjusted 

death rates

(Using the 1990 Census Resident population as the standard population for age-sex adjusting)
Mortality, Page 12

 Table 2.1 (Continued): Historical and Assumed Rates of Reduction in Mortality1

2004 2007 2008 2009 2011 2011 2013

1900-2009 1982-2009

Trustees 

Alternative 22

 Technical 

Panel3

Trustees 

Alternative 24

Trustees 

Alternative 25

Trustees 

Alternative 26

 Technical 

Panel7

Trustees 

Alternative 28

0 - 14 3.15 2.34 1.55 1.00 1.57 1.55 1.56 1.26 1.57

15 - 64 1.38 1.25 0.78 1.00 1.00 0.99 0.96 1.26 0.98

65 & Over 0.79 0.77 0.69 1.00 0.65 0.71 0.66 1.26 0.64

1Rates of reduction are the average of male and female annual rates of decline in age-adjusted central death rates. The rates for the period 1900-2009 are a weighted

 average of rates for five separate distinct periods of change.

2The 2004 Trustees ultimate intermediate assumptions are for the period 2028-2078.

3The 2007 Technical Panel ultimate assumptions are for the period 2031-2081.

4The 2008 Trustees ultimate intermediate assumptions are for the period 2032-2082.

5The 2009 Trustees ultimate intermediate assumptions are for the period 2033-2083.

6The 2011 Trustees ultimate intermediate assumptions are for the period 2035-2085.

7The 2011 Technical Panel ultimate assumptions are for the period 2035-2085.

8The 2013 Trustees ultimate intermediate assumptions are for the period 2037-2087.

Social Security Administration

Office of the Chief Actuary

July 22, 2015

Historical average 

annual percent 

reductions in 

age-sex-adjusted 

death rates

(Using the 2000 Census Resident population as the standard population for age-sex adjusting)

Assumed ultimate annual percent reductions in age-sex-adjusted death rates
Mortality, Page 13

Table 2.1 (Continued): Historical and Assumed Rates of Reduction in Mortality1

2013 2014 2015

1900-2011 1982-2011

Trustees 

Alternative 22

Trustees 

Alternative 23

Trustees 

Alternative 24

0 - 14 3.13 2.33 1.57 1.57 1.57

15 - 64 1.33 1.32 1.00 1.00 1.00

65 & Over 0.78 0.82 0.63 0.62 0.61

1Rates of reduction are the average of male and female annual rates of decline in age-adjusted central death rates. The rates for the period 1900-2010 are a weighted

 average of rates for five separate distinct periods of change.

2The 2013 Trustees ultimate intermediate assumptions are for the period 2037-2087.

3The 2014 Trustees ultimate intermediate assumptions are for the period 2038-2088.

4The 2015 Trustees ultimate intermediate assumptions are for the period 2039-2089.

Social Security Administration

Office of the Chief Actuary

July 22, 2015

(Using the 2010 Census Resident population as the standard population for age-sex adjusting)

Historical average 

annual percent 

reductions in 

age-sex-adjusted 

death rates

Assumed ultimate annual percent reductions in age-sex-adjusted death rates
Mortality, Page 14

Table 2.2: Average Annual Percent Reductions in Age-Adjusted Central Death Rates: for the 2015 Trustees Report 1

Sex Age 1900-1936 1936-1954 1954-1968 1968-1982 1982-2011 1900-2011 2011-2039 2011-2089 2039-2089

Male 0-14 2.91 4.79 1.65 4.33 2.42 3.12 1.60 1.57 1.56

15-49 1.46 3.01 -0.25 2.21 1.13 1.51 1.00 0.92 0.88

50-64 0.42 0.96 -0.13 2.28 1.70 1.01 1.15 1.09 1.06

65-84 0.20 1.16 -0.11 1.46 1.65 0.86 1.17 0.91 0.76

85+ 0.22 1.21 -0.89 1.56 0.28 0.43 0.70 0.57 0.49

65+ 0.21 1.17 -0.37 1.50 1.13 0.70 0.97 0.75 0.64

Total 0.67 1.49 -0.25 1.78 1.25 0.98 1.01 0.83 0.73

Female 0-14 3.14 5.06 1.72 4.15 2.20 3.16 1.55 1.57 1.58

15-49 1.53 4.68 0.28 2.91 0.45 1.79 0.93 0.94 0.94

50-64 0.71 2.57 0.76 1.72 1.22 1.28 1.19 1.11 1.06

65-84 0.35 2.05 1.06 2.03 0.75 1.04 1.00 0.81 0.71

85+ 0.23 1.21 0.13 2.06 0.04 0.56 0.60 0.51 0.47

65+ 0.31 1.74 0.69 2.04 0.45 0.85 0.81 0.67 0.59

Total 0.79 2.31 0.70 2.11 0.60 1.15 0.89 0.75 0.68

Total 0-14 3.01 4.90 1.68 4.26 2.33 3.13 1.58 1.57 1.57

15-49 1.49 3.69 -0.06 2.44 0.91 1.63 0.97 0.93 0.90

50-64 0.55 1.62 0.19 2.08 1.52 1.13 1.17 1.09 1.06

65-84 0.28 1.60 0.42 1.72 1.25 0.95 1.09 0.86 0.74

85+ 0.23 1.21 -0.22 1.86 0.14 0.52 0.64 0.53 0.48

65+ 0.26 1.46 0.19 1.77 0.82 0.78 0.89 0.71 0.61

Total 0.73 1.88 0.22 1.95 0.97 1.07 0.95 0.80 0.71

1Using the 2010 Census Resident population as the standard population for age adjusting

Social Security Administration

Office of the Chief Actuary

July 22, 2015

Historical Period (last year of final data is 2011) Intermediate Alternative
Mortality, Page 15

Table 2.2 (Continued): Average Annual Percent Reductions in Age-Adjusted Central Death 

Rates: for the 2015 Trustees Report 1

Sex Age 2011-2039 2011-2089 2039-2089 2011-2039 2011-2089 2039-2089

Male 0-14 0.81 0.80 0.79 2.59 2.56 2.54

15-49 0.51 0.47 0.45 1.60 1.48 1.41

50-64 0.55 0.57 0.58 1.86 1.67 1.56

65-84 0.64 0.52 0.44 1.77 1.32 1.07

85+ 0.31 0.29 0.27 1.14 0.88 0.73

65+ 0.50 0.41 0.37 1.49 1.11 0.90

Total 0.51 0.45 0.41 1.58 1.24 1.05

Female 0-14 0.79 0.79 0.80 2.53 2.57 2.59

15-49 0.43 0.47 0.49 1.55 1.52 1.50

50-64 0.59 0.58 0.57 1.91 1.70 1.59

65-84 0.53 0.46 0.41 1.53 1.19 1.00

85+ 0.22 0.24 0.26 1.02 0.81 0.69

65+ 0.39 0.36 0.34 1.29 1.00 0.84

Total 0.42 0.40 0.39 1.41 1.13 0.98

Total 0-14 0.80 0.80 0.79 2.56 2.56 2.57

15-49 0.48 0.47 0.47 1.58 1.49 1.45

50-64 0.57 0.57 0.58 1.88 1.68 1.57

65-84 0.59 0.49 0.43 1.65 1.25 1.03

85+ 0.25 0.26 0.26 1.07 0.83 0.70

65+ 0.44 0.38 0.35 1.39 1.06 0.87

Total 0.47 0.43 0.40 1.50 1.19 1.02

1Using the 2010 Census Resident population as the standard population for age adjusting

Social Security Administration

Office of the Chief Actuary

July 22, 2015

Low-Cost Alternative High-Cost Alternative
Mortality, Page 16

Table 2.3: Average Annual Rates of Reduction in Central 

Death Rates by Age Group, Sex, and Cause 

2014 TR 2015 TR 2014 TR 2015 TR 

1979 to 2011 2001 to 2011 2038 to 2088 2039 to 2089 1979 to 2011 2001 to 2011 2038 to 2088 2039 to 2089

Under Age 15

Cardiovascular Disease 2.73 2.01 2.3 2.3 2.58 2.29 2.3 2.3

Cancer 2.48 2.16 1.5 1.5 2.01 1.84 1.5 1.5

Violence 2.89 2.52 1.0 1.0 2.38 2.46 1.0 1.0

Respiratory Disease 2.65 0.63 2.0 2.0 2.73 0.97 2.0 2.0

Other 2.37 1.70 1.7 1.7 2.25 1.34 1.7 1.7

Resulting Total ** 2.50 1.84 1.56 1.56 2.29 1.55 1.58 1.58

Ages 15 - 49

Cardiovascular Disease 2.03 1.54 1.5 1.5 1.22 1.38 1.5 1.5

Cancer 1.83 2.35 1.5 1.5 1.64 1.89 1.5 1.5

Violence 0.86 0.47 0.7 0.7 0.11 -0.62 0.7 0.7

Respiratory Disease 0.80 0.26 0.5 0.5 -0.25 -0.83 0.5 0.5

Other 0.29 3.26 0.8 0.8 -0.47 1.49 0.8 0.8

Resulting Total ** 1.12 1.51 0.88 0.88 0.57 0.88 0.94 0.94

Ages 50 - 64

Cardiovascular Disease 3.15 2.65 2.2 2.2 2.67 3.10 2.2 2.2

Cancer 1.62 1.85 1.5 1.5 1.35 2.05 1.5 1.5

Violence 0.30 -2.43 0.5 0.5 -0.33 -3.21 0.5 0.5

Respiratory Disease 1.16 0.48 0.7 0.7 -0.52 0.52 0.7 0.7

Other -0.39 -0.50 0.6 0.6 -0.44 0.06 0.6 0.6

Resulting Total ** 1.71 1.12 1.06 1.06 1.17 1.42 1.06 1.06

Ages 65 - 84

Cardiovascular Disease 3.21 4.51 2.2 2.2 2.83 4.47 2.2 2.2

Cancer 0.78 1.91 0.9 0.9 -0.13 1.18 0.9 0.9

Violence 0.67 0.27 0.5 0.5 -0.02 -0.07 0.5 0.5

Respiratory Disease 0.56 1.80 0.3 0.3 -2.17 0.66 0.3 0.3

Other -0.79 -0.34 0.3 0.3 -1.55 -0.58 0.3 0.3

Resulting Total ** 1.56 2.32 0.77 0.76 0.72 1.78 0.72 0.71

Ages 85 and older

Cardiovascular Disease 1.63 3.52 1.2 1.2 1.79 3.87 1.2 1.2

Cancer -0.36 1.32 0.5 0.5 -0.58 0.53 0.5 0.5

Violence -0.64 -0.11 0.3 0.3 -1.12 -1.62 0.3 0.3

Respiratory Disease -0.76 2.57 0.2 0.2 -1.98 1.85 0.2 0.2

Other -2.34 -2.11 0.2 0.2 -3.26 -2.51 0.2 0.2

Resulting Total ** 0.24 1.55 0.51 0.49 0.06 1.24 0.48 0.47

Total

Cardiovascular Disease 2.63 3.73 2.33 3.96

Cancer 0.86 1.81 0.40 1.36

Violence 0.67 -0.10 -0.02 -0.98

Respiratory Disease 0.20 1.92 -1.77 1.00

Other -0.85 -0.54 -1.60 -1.02

Resulting Total ** 1.21 1.81 0.74 0.73 0.60 1.48 0.69 0.68

Social Security Administration

Office of the Chief Actuary

Female

Male Female

Alternative II* Alternative II*

Male

Female

Historical Historical

Female

Male

* Alternative 1 is 1/2 times Alternative 2; Alternative 3 is 5/3 times Alternative 2.

July 22, 2015

Male Female

Male Female

Male

**Resulting total represents average annual percent reduction in age-adjusted death rates for the last 50 years of the 75 year projection period.
Mortality, Page 17

Table 2.4: Age-Sex-Adjusted Central Death Rates

(per 100,000 population)

Year 2014 TR 2015 TR

1900 2,684.3 2,684.3

1910 2,495.9 2,495.9

1920 2,304.5 2,304.5

1930 2,094.9 2,094.9

1940 1,919.8 1,919.8

1945 1,716.6 1,716.6

1950 1,561.9 1,561.9

1955 1,453.8 1,453.8

1960 1,454.3 1,454.3

1965 1,428.8 1,428.8

1970 1,340.0 1,340.0

1975 1,204.8 1,204.8

1980 1,136.9 1,136.9

1985 1,081.0 1,081.0

1990 1,021.3 1,021.3

1991 1,007.7 1,007.7

1992 992.7 992.7

1993 1,016.4 1,016.4

1994 1,004.1 1,004.1

1995 1,001.5 1,001.5

1996 987.8 987.8

1997 971.9 971.9

1998 963.8 963.8

1999 970.6 970.6

2000 960.7 960.7

2001 951.1 951.1

2002 947.0 947.0

2003 933.4 933.4

2004 898.9 898.9

2005 901.3 901.3

2006 876.1 876.1

2007 856.8 856.8

2008 857.0 857.0

2009 827.1 827.1

2010 821.3 821.3

2011 820.1 1 819.4

2012 801.9 1 810.0 1

2013 790.6 2 792.7 1

2014 779.8 2 781.8 2

2014 TR 2015 TR 2014 TR 2015 TR

2015 784.2 778.7 770.0 771.3 755.8 763.9

2020 768.1 763.3 730.2 730.1 691.6 696.4

2025 751.7 747.3 697.3 697.1 641.5 645.5

2030 735.4 731.4 667.6 667.6 598.5 602.4

2040 703.9 700.5 614.6 615.0 526.3 530.1

2050 674.5 671.5 568.1 568.9 467.6 471.4

2060 646.9 644.4 527.1 528.2 419.0 422.8

2070 621.2 619.0 490.8 492.2 378.4 382.2

2080 597.0 595.2 458.4 460.1 344.0 347.8

2090 574.3 572.9 429.5 431.4 314.5 318.3

2100 553.0 551.9 403.5 405.6 289.0 292.8

1 Estimated Social Security Administration

2

 Estimate, Intermediate Alternative Office of the Chief Actuary

Alternative I Alternative II Alternative III

July 22, 2015

2014 TR 2015 TR
Mortality, Page 18

Chart 2.1: Historical United States Age-Sex-Adjusted Central Death Rates from 1900-2011

0

500

1000

1500

2000

2500

3000

1900 1905 1910 1915 1920 1925 1930 1935 1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 Annual Deaths per 100,000

Year

Social Security Administration

Office of the Chief Actuary

July 22 2015
Mortality, Page 19

Chart 2.2: Difference between Male and Female Annual Percent Reduction in Age-Adjusted 

Death Rates for Population 65+ 

(based on Medicare data)

-2.0%

-1.5%

-1.0%

-0.5%

0.0%

0.5%

1.0%

1.5%

2.0%

1969 1974 1979 1984 1989 1994 1999 2004 2009 Difference in Rates (%)

Year

Social Security Administration

Office of the Chief Actuary

July 22, 2015
Immigration, Page 1

3. IMMIGRATION

ASSUMPTIONS FOR THE 2015 TRUSTEES REPORT

OFFICE OF THE CHIEF ACTUARY, SSA

TABLE OF CONTENTS PAGE

3.1 SUMMARY ................................................................................................................................. 2

3.2 LEGAL IMMIGRATION .............................................................................................................. 3

3.3 LEGAL EMIGRATION ................................................................................................................ 4

3.4 NET LEGAL IMMIGRATION ...................................................................................................... 5

3.5 OTHER IMMIGRATION .............................................................................................................. 5

3.6 RECOMMENDATIONS OF PREVIOUS TECHNICAL PANELS AND OTHER PROJECTIONS........... 7

TABLE 3.1: ANNUAL IMMIGRATION ASSUMPTIONS FOR THE SOCIAL SECURITY AREA POPULATION..............................9

TABLE 3.2: LEGAL IMMIGRANTS ADMITTED TO THE UNITED STATES: FISCAL YEARS 1966-1991 ...............................10

TABLE 3.3: LEGAL IMMIGRATION LIMITS FOR FISCAL YEARS BEGINNING 1995 ..........................................................11

TABLE 3.4: LEGAL IMMIGRANTS ADMITTED TO THE UNITED STATES: FISCAL YEARS BEGINNING 1985 .....................12
Immigration, Page 2

3.1 Summary

For the 2015 Trustees Report, there are slight changes to the ultimate immigration assumptions 

from those used in the 2014 Trustees Report as a result of the President’s 2014 executive actions 

on immigration. Table 3.1 displays the annual immigration levels for the 2015 Trustees Report 

as well as those used in the 2014 Trustees Report. Compared to the levels assumed in the 2014 

Trustees Report, the Trustees assume the level of legal immigration will be 10,000 higher and 

other-than-legal immigration will be 50,000 lower for all three alternatives. Additionally, 

historical data updates and revised paths to the ultimate assumptions result in different otherthan-legal population projections. The effect on the long-range OASDI actuarial balance, under 

the intermediate alternative, of the changes excluding the President’s 2014 executive actions on 

immigration result in a cost of 0.04 percent of taxable payroll. The executive actions on 

immigration result in an increase (improvement) of the OASDI actuarial balance of 0.02 percent 

of payroll.

Historically, the annual number of legal immigrants (persons becoming legal permanent 

residents) has risen substantially, averaging around 1.1 million persons per year since 2005. 

Based on this experience and the belief that the number of future legal immigrants in the 

category of immediate relatives of U.S. citizens will be close to current levels, the Trustees 

intermediate ultimate assumption is 1.06 million new legal permanent residents per year for the 

2015 Trustees Report. There was no change to the assumption that legal emigration out of the 

Social Security area will be 25 percent of the number of the legal immigrants, or 265,000 per 

year, ultimately. 

For other-than-legal (“other”) immigration, the Trustees assume no change to the immigration 

projection model introduced during the 2014 Trustees Report. The model projects the annual 

other immigration flows by splitting them into three main components: (1) the other immigrants 

entering the Social Security area each year, (2) those who leave the stock of other immigrants 

and move outside the Social Security area, and (3) the other immigrants that adjust status to 

become legal permanent residents, thereby leaving other immigrant status. The net other 

immigration is equal to the gross level of other immigration, less other emigration out of the 

Social Security area, and less those who adjust status to become legal permanent residents.

The model continues to project these annual other immigrant flows and further separates the 

other immigrants into three specific categories: (1) those immigrants who have temporary legal 

status (“nonimmigrant”), (2) those who never had temporary legal status (“never-authorized”), 

and (3) those who originally entered legally as a nonimmigrant but overstayed their visa (“visaoverstayers”). 

Using this model of other immigration, the level of net other immigration, under the intermediate 

alternative, is assumed to be about 670,000 persons for 2015, 600,000 persons for 2020, 340,000

persons for 2040, and 290,000 persons for 2080. The average level of net other immigration 

during the 75-year projection period is approximately 360,000 persons per year. The following 

table presents the projected net numbers of immigrants for the intermediate alternative. 
Immigration, Page 3

Annual Net Immigration: Alternative II Levels for the 

2015 Trustees Report

Year Legal Other Total

2015 795,000 670,000 1,465,000

2020 795,000 600,000 1,395,000

2030 795,000 395,000 1,190,000

2040 795,000 340,000 1,135,000

2050 795,000 315,000 1,110,000

2060 795,000 300,000 1,095,000

2070 795,000 290,000 1,085,000

2080 795,000 290,000 1,085,000

 Notes: Totals do not necessarily equal the sums of rounded components.

 Levels rounded to the nearest 5,000.

3.2 Legal Immigration

The term legal immigration for a given year refers to the number of persons granted authorization 

to live and work in the United States on a permanent basis. These individuals are referred to as 

legal permanent residents (LPRs). Many individuals are admitted to the country legally but on a 

temporary basis. These individuals are included as other immigrants and are discussed in the 

following sections of this paper.

Legal immigration has been a very important element in the growth of the United States 

population. For the period 1870 through 1930, the population averaged about 13 percent foreign 

born. The Census Bureau estimates that the percentage of the civilian non-institutionalized 

population that is foreign born declined to a low of about 5 percent in the 1970 Census, rose to 

about 8 percent in the 1990 Census, and was estimated to be approximately 13.1 percent in the 

2013 American Community Survey.

Data on the number of legal immigrants admitted to the U.S., which include U.S. possessions 

and territories and Armed Service posts abroad, are obtained from the Office of Immigration 

Statistics (OIS), a component of the Department of Homeland Security (DHS). Legal 

immigration averaged nearly one million per year for the period 1904 through 1914. Legal 

immigration decreased greatly during World War I and following the adoption of quotas based 

on national origin in 1921. The economic depression in the 1930's caused an additional, but 

temporary, decrease that resulted in more emigration than immigration. Annual legal 

immigration increased after World War II to around 200,000 to 300,000 persons and stayed at 

that level through the 1950's and into the 1960's. With the Immigration Act of 1965 and other 

related changes, annual legal immigration increased to about 400,000 and remained fairly stable 

until 1977. Between 1977 and 1990, legal immigration (excluding aliens admitted under the 

Immigration Reform and Control Act of 1986 [IRCA]) averaged approximately 580,000 per 

year. This increase was due to the increase in the numbers of relatives admitted and to the large 

numbers of refugees and political asylees admitted during this period. Table 3.2 lists legal U.S. 

immigration for fiscal years 1966 through 1991, reflecting the immigration categories established 

in the 1965 Act. 
Immigration, Page 4

The Immigration Act of 1990, which took effect in fiscal year 1992, restructured the immigration 

categories and substantially increased the number of immigrants that may legally enter the 

United States each year. For fiscal years 1995 and later, the 1990 law specified an annual limit 

that could range between 421,000 and 675,000 for certain categories of immigrants. These 

categories and their limits include those admitted based on: family-sponsored preference 

(226,000 to 480,000), employment-based preference (140,000) and diversity (55,000). Other 

categories of immigrants, such as refugees, are subject to separate limits. The Real ID Act of 

2005 eliminated the numerical limit on asylees and no numerical limitation exists for immediate 

relatives of U.S. citizens. For each of the numerically limited categories, the limits may be 

adjusted annually based on unused amounts from prior years or other categories. Table 3.3 

displays these unadjusted limits and the adjusted limits for each fiscal year 1995-2013.

The annual level of total legal immigration and the levels by category can vary considerably 

from year to year as shown in table 3.4. For fiscal years 1998 and 1999, annual immigration was 

about 650,000, the lowest level since the 1990 Act went into effect. This drop is attributed to a 

backlog in the process caused mainly by the longer time required to process the affidavit of 

support and the shifting of responsibilities from the Department of State to the Department of 

Homeland Security. Legal immigration was 841,000 in 2000 and over 1,000,000 in 2001 and 

2002. These levels in 2000 – 2002 were also significantly above the low levels in 1998 and 1999, 

mainly due to the efforts to reduce the backlog of pending immigration applications. In 2003, 

legal immigration declined to a level of 704,000 due to a slowdown in processing because of 

increased security checks. Since then, the level increased dramatically and peaked at a level of 

1,266,000 persons in 2006 before declining 16.9 percent to 1,052,000 in 2007. However, the 

decline in 2007 is attributed to an unanticipated spike in naturalization applications that 

temporarily shifted resources away from processing immigration applications. In 2008, the level 

increased slightly from the 2007 level, to 1,107,000. In 2009, there was another slight increase, 

to 1,131,000. From 2010 – 2013, total legal immigration declined from 1,043,000 in 2010 to 

991,000 in 2013. For the intermediate assumptions, the Trustees assume that the future legal 

immigration levels will average approximately 1.06 million persons per year.

It is possible that future global economic conditions assumed under the high-cost alternative 

and/or less favorable attitudes toward immigration could result in generally lower immigration. 

Therefore, the Trustees assume an ultimate level of 860,000 legal immigrants per year for the 

high-cost (low immigration) alternative. On the other hand, the significant increase in the 

number of immediate relatives admitted in recent years and the uncertainty of the number of 

refugees and asylees permits the possibility of annual immigration substantially higher than 

1,060,000 persons per year. Therefore, the ultimate level for the low-cost (high immigration) 

alternative is 1,260,000 persons per year.

3.3 Legal Emigration

Statistics on emigration are sparse and most analysis is based largely on estimates. Research 

done by the Census Bureau, the OIS, and other experts suggests that annual emigration may 

generally be in the range of 20-40 percent of annual legal immigration. Expected emigration 

from the Social Security area should be less than emigration from the United States, especially at 

the older ages. This is primarily because most individuals who leave the United States having 
Immigration, Page 5

achieved fully insured status are still eligible to receive OASDI benefits and thus are still 

considered to be in the Social Security area population. For the 2014 Trustees Report, the 

assumed ratio of emigration to immigration was 20, 25, and 30 percent for the low-cost, 

intermediate, and high-cost alternatives, respectively. The same ratios of emigration to 

immigration are assumed for the 2015 Trustees Report.

3.4 Net Legal Immigration

Combining the levels of legal immigration with the ratios for legal emigration yields ultimate 

levels of net legal immigration of 1,008,000, 795,000, and 602,000 per year for the low-cost, 

intermediate, and high-cost alternatives, respectively. 

3.5 Other Immigration

The term “other immigration” refers to persons entering the United States in a manner other than 

lawfully admitted for permanent residence. This population consists of three components: 

1) Nonimmigrants who are defined, according to the OIS, as foreign nationals that enter the 

U.S. with authorization to stay for a temporary period of time and for a specific purpose 

such as students and exchange visitors, temporary workers, and diplomats and other 

representatives. 

2) Those who are unauthorized on entry and were never previously legally authorized to be

residing in the United States (“never-authorized”).

3) Those who at one point had temporary legal authorization to be residing in the United 

States but have overstayed their visas (“visa-overstayers”).

The stock of the other immigrant population is included in the starting year population level for 

our projections, in accordance with the official policy of the Census Bureau to enumerate all 

persons residing in the U.S., as well as to provide a basis for estimating the total labor force in 

the United States and total births in the Social Security area. 

During the 1990s there was rapid growth in the size of the other immigrant population. In a joint 

project, the OIS and the Census Bureau examined the size of the unauthorized immigrant 

population between October 1988 and October 1992. In 1988 there were over 4 million 

unauthorized immigrants residing in the United States. Not counting those who would be 

subsequently legalized under the Immigration Reform and Control Act (IRCA) program, it is 

estimated that there were 2.2 million unauthorized immigrants in the population as of October 

1988. At the time of the 1990 Census, 2.6 million persons were estimated to be unauthorized, 

again excluding those who would subsequently be legalized under the IRCA. (The total 

unauthorized population in 1990 was, roughly, 5.3 million.) Subsequent estimates suggest an 

increase to 3.4 million for October 1992 and approximately 5.0 million for October 1996. The 

rapid rise in the other immigrant population between 1990 and 1996 reflected the continued 

inflow of other immigrants combined with a decreased number leaving this status, due to the 

reduced stock of other immigrants that resulted from the IRCA.
Immigration, Page 6

The 2000 Census gave evidence that other immigration since 1990 had been consistently 

underestimated. In producing intercensal estimates of the U.S. population between the 1990 and 

2000 Census, the Census Bureau estimated the average level of annual net other immigration to 

be approximately 550,000. For 2000, DHS estimated a total other stock of 9.9 million. Based on 

DHS estimates, the total stock was 12.2 million in 2005, then increased to a peak of 14.1 million 

in 2008, and then decreased to 13.3 million by 2012.

The OCACT other immigration model makes explicit estimates of the following categories:

 The annual numbers of new-arrival other immigrants who enter as never-authorized and 

who enter legally as nonimmigrants;

 The annual number of non-immigrants who become visa-overstayers;

 The annual numbers of other emigrants (those leaving the Social Security area) who were

never-authorized, nonimmigrants, or visa-overstayers; and

 The annual numbers of adjustments of status who were never-authorized, nonimmigrants,

or visa-overstayers.

For the 2015 Trustees Report, the Trustees assume the ultimate number of new other immigrants 

to be 50,000 lower per year than the 2014 Trustees Report due to the President’s 2014 executive 

actions on immigrations. Thus, the Trustees assume an ultimate level of 1,350,000 per year 

under the intermediate projections. Due to the projected economic recovery, the Trustees 

assume a slow increase in the number of new other immigrants from current levels to 1,550,000 

in 2018 and 2019 before a gradual decrease to the ultimate level of 1,350,000 in 2022. It is 

possible that the ultimate level will be higher than 1,350,000 in the future, as other immigrants 

already in the U.S. may help family members or additional other immigrants enter the country 

and the demand for other immigrant labor in the economy may increase. Thus, the Trustees 

assume an ultimate level of 1,650,000 per year under the low-cost (high immigration) scenario. 

Due to the possibility of an increased willingness of the government to pursue deportation of 

unauthorized immigrants or withhold services from them and to crack down on those who 

employ them, the Trustees assume an ultimate level of 1,050,000 under the high-cost (low 

immigration) scenario. 

While we estimate the average annual other emigration level (departures from the Social 

Security area) during 2008 through 2010 to be around 435,000, we believe this number will rise 

throughout the projection period. As the stock of the other immigrant population rises, more 

emigration is likely to occur. Thus, we estimate the other emigration as a function of the 

population at risk. We developed rates of emigration by age and sex for the never-authorized, 

the nonimmigrants, and the overstayers based on the number of exits from each of these 

categories estimated to have occurred during the period 2008 through 2011. Ideally, these rates 

would be developed by age, sex, and duration of stay in the country. Unfortunately, at this time, 

data are too sparse to develop accurate estimates of the current stock by duration of stay. 

Applying the method described above results in increasing levels of emigration1throughout the 

projection period. Under the intermediate alternative, the gross emigration rate (number of other 

 

1 As the stock begins to mature, we expect to see higher numbers of other immigrants in the population and thus 

higher levels of emigration, particularly at the ages 35 and over. The current stock of other immigrants is centered 
Immigration, Page 7

emigrants divided by the stock of other) is about 2.0 percent at the start of the projection period, 

increasing to a maximum of about 2.4 percent by 2035, but declines to about 2.2 percent at the 

end of the 75-year projection period. 

Another component of the immigration model takes into account the following two ways 

immigrants attain legal permanent resident status:

1) New-arrival LPRs are persons who file an application to become an LPR with the 

Department of State while living outside of the United States and become an LPR upon 

entry.

2) Adjustments of Status2are persons who are already living in the United States as 

temporary workers, students, or unauthorized immigrants and apply and receive an 

adjustment of status to an LPR. 

Historically, the adjustment of status category has been a substantial portion of all new LPRs. In 

the past, approximately 50 percent of all new LPRs were people that had already been in the 

country as a temporary worker, foreign student, or unauthorized immigrant and who filed an 

application for adjustment to LPR status. However, the recent trend shows this percentage 

decreasing to under 50 percent. Thus, the Trustees assume a little over 40 percent of future 

individuals becoming LPRs will be adjustments of status from the other immigrant population.

3.6 Recommendations of Previous Technical Panels and Other Projections

The levels of immigration recommended by recent Technical Panels (2003, 2007, and 2011) 

appointed by the Social Security Advisory Board are substantially higher than the levels assumed

for the 2015 Trustees Report. For the intermediate assumptions, the 2003 Technical Panel

recommended a continuing annual growth rate in net total immigration equal to approximately 

1/2 the annual growth rate in the total population through the next 75 years. Under this 

specification, total net immigration would have been projected to reach 1.5 million by 2065, with 

continuing increases thereafter.3 

The 2007 Technical Panel recommended setting net total immigration equal to 1.35 million for 

2007, with increases of 1.0 percent per year for the first 25 years of the projection period and 

increases of 0.5 percent per year increases thereafter. This would have resulted in a net

immigration flow of nearly 2.2 million by the end of the projection period.

 

very heavily at the younger ages. We believe this concentration at the younger ages is due to (1) the relatively high 

levels of other immigration that began in the late 1990’s (entering at relatively young ages) and (2) the effects of the 

IRCA legislation in the late 1980’s (which removed largely older individuals with required substantial durations of 

residence in the country). These reasons result in a current stock of other population that is relatively young of age 

and low in duration of stay in the country. 

2 The Department of Homeland Security also considers refugees and asylees to be adjustments of status, but for the 

purposes of our model, we treat these categories as new arrivals.

3 All results displayed in this section are based on that current year’s Trustees Report model. For example, the result 

using the 2003 Technical Panel recommendation is based on the 2003 Trustees Report model.
Immigration, Page 8

The 2011 Technical Panel recommended setting net immigration equal to 0.32 percent of the 

total population for all years after 2025. This would have resulted in a net immigration flow of 

nearly 1.63 million by the end of the projection period.

This increase in the level of total net immigration recommended by these panels reflects a 

number of factors. One factor is that each panel includes the assumption of continuing changes 

in immigration law to allow more immigrants as the population increases. Historically, the 

Trustees, as well as other Federal Government entities, have assumed that future immigration 

will be consistent with current law and that changes based on potential future legislation should 

not be reflected until enactment. Reflecting the possibility of future changes in immigration law 

is not unreasonable if there is a conviction that such changes are truly expected to occur and this 

change in the basis for projecting is fully disclosed. On the other hand, presuming such changes 

could result in the peculiar situation where the Trustees would need to change assumptions in the 

future because immigration law had not been modified. On balance, the Trustees retained the 

practice of reflecting changes in the immigration law only upon enactment. Another factor is the 

potential number of immigrants entering the U.S. The Trustees recognized that birth rates have 

dropped in several countries that supply significant numbers of immigrants to the U.S. Most of 

those countries, particularly Mexico, have seen drops in birth rates since 1990 and will likely 

average less emigration in the future.

In their 2014 projections, the Congressional Budget Office (CBO) assumes an ultimate annual 

net immigration of 3.2 immigrants per 1,000 members of the U.S. population.4 This is the same 

assumption recommended by the 2011 Technical Panel. Specifically, CBO reports that this 

assumption results in net immigration of 1.2 million people in 2025 and 1.3 million people in 

2039. Comparing with Census, the middle series of the 2014 National Population Projections 

results in net immigration of 1.4 million people in 2040.5The Trustees assumptions for the 

intermediate alternative of the 2015 Trustees Report result in net immigration of 1.2 million 

people in 2025 and 1.1 million people in 2039 and 2040.

 

4

See http://www.cbo.gov/sites/default/files/45471-Long-TermBudgetOutlook_7-29.pdf

5

See http://www.census.gov/population/projections/files/methodology/methodstatement14.pdf
Immigration, Page 9

Table 3.1: Annual Immigration Assumptions for the Social Security Area Population

(All values rounded to the nearest 5,000 immigrants)

Alternative Year Gross Legal Net Legal Gross Other Net Other Alternative Year Gross Legal Net Legal Gross Other Net Other

Low Cost: 2015 1,200,000 960,000 1,600,000 660,000 Low Cost: 2015 1,185,000 950,000 1,500,000 695,000

2030 1,250,000 1,000,000 1,700,000 495,000 2030 1,260,000 1,010,000 1,650,000 530,000

2040 1,250,000 1,000,000 1,700,000 410,000 2040 1,260,000 1,010,000 1,650,000 440,000

2050 1,250,000 1,000,000 1,700,000 370,000 2050 1,260,000 1,010,000 1,650,000 400,000

2060 1,250,000 1,000,000 1,700,000 350,000 2060 1,260,000 1,010,000 1,650,000 375,000

2070 1,250,000 1,000,000 1,700,000 340,000 2070 1,260,000 1,010,000 1,650,000 365,000

2080 1,250,000 1,000,000 1,700,000 335,000 2080 1,260,000 1,010,000 1,650,000 360,000

2090 1,250,000 1,000,000 1,700,000 335,000 2090 1,260,000 1,010,000 1,650,000 355,000

Intermediate: 2015 1,050,000 790,000 1,400,000 535,000 Intermediate: 2015 1,060,000 795,000 1,400,000 670,000

2030 1,050,000 790,000 1,400,000 370,000 2030 1,060,000 795,000 1,350,000 395,000

2040 1,050,000 790,000 1,400,000 315,000 2040 1,060,000 795,000 1,350,000 340,000

2050 1,050,000 790,000 1,400,000 295,000 2050 1,060,000 795,000 1,350,000 315,000

2060 1,050,000 790,000 1,400,000 280,000 2060 1,060,000 795,000 1,350,000 300,000

2070 1,050,000 790,000 1,400,000 275,000 2070 1,060,000 795,000 1,350,000 290,000

2080 1,050,000 790,000 1,400,000 270,000 2080 1,060,000 795,000 1,350,000 290,000

2090 1,050,000 790,000 1,400,000 270,000 2090 1,060,000 795,000 1,350,000 285,000

High Cost: 2015 900,000 630,000 1,100,000 315,000 High Cost: 2015 910,000 635,000 1,100,000 445,000

2030 850,000 595,000 1,100,000 295,000 2030 860,000 600,000 1,050,000 310,000

2040 850,000 595,000 1,100,000 250,000 2040 860,000 600,000 1,050,000 265,000

2050 850,000 595,000 1,100,000 230,000 2050 860,000 600,000 1,050,000 245,000

2060 850,000 595,000 1,100,000 220,000 2060 860,000 600,000 1,050,000 235,000

2070 850,000 595,000 1,100,000 215,000 2070 860,000 600,000 1,050,000 225,000

2080 850,000 595,000 1,100,000 210,000 2080 860,000 600,000 1,050,000 220,000

2090 850,000 595,000 1,100,000 210,000 2090 860,000 600,000 1,050,000 220,000

Social Security Administration

Office of the Chief Actuary

July 22, 2015

Values Used for 2014 Trustees Report Values Used for 2015 Trustees Report
Immigration, Page 10

Table 3.2: Legal Immigrants Admitted to the United States: Fiscal Years 1966-1991

(in thousands)

Reflecting Categories Established in the 1965 Immigration Act

Fiscal 

Year IRCA1

Total non 

IRCA

Numerically 

Limited 2

Western 

Hemisphere 3

Immediate Relatives 

of Citizens

Refugees & 

Asylees

Other Specially 

Legislated Immigrants 4

1966 — 323 126 148 39 4 6

1967 — 362 153 125 47 30 7

1968 — 454 156 154 44 95 6

1969 — 359 291 — 60 1 7

1970 — 373 287 — 79 — 7

1971 — 370 281 — 81 — 8

1972 — 385 284 — 86 — 15

1973 — 400 283 — 101 — 16

1974 — 395 274 — 105 — 16

1975 — 386 282 — 92 — 13

1976 — 399 285 — 102 — 12

1976 — 104 73 — 28 — 3

1977 — 462 277 — 106 68 12

1978 — 601 341 — 126 122 12

1979 — 460 279 — 138 32 11

1980 — 531 289 — 158 76 8

1981 — 597 330 — 152 107 7

1982 — 594 260 — 168 157 9

1983 — 560 269 — 178 103 10

1984 — 544 262 — 183 92 7

1985 — 570 264 — 204 95 6

1986 — 602 267 — 223 104 7

1987 — 602 271 — 219 92 20

1988 — 643 264 — 219 82 78

1989 479 612 280 — 218 84 30

1990 880 656 298 — 232 97 29

1991 1,123 704 294 — 237 139 34

1

 This category includes those aliens admitted under the Immigration Reform and Control Act of 1986.

2

 Legal limits on immigration visas were 170,000 per fiscal year before 1969, 290,000 per fiscal year for 1969 through 1979, 

 280,000 for fiscal year 1980, and 270,000 for fiscal years 1981 and later. Includes additional visas starting 1989.

3

 Natives of Western Hemisphere countries, their children and spouses, Act of October 3, 1965. This category became

 numerically limited to 120,000 starting fiscal year 1969.

4

 This category consists mainly of children born abroad to alien residents, ministers and their families, beginning 1971,

 spouses of U.S. citizens who entered as fiances and their children, and beginning 1988 Amerasians, special

 Cuban / Haitian entrants, and aliens in the U.S. since 1972.

Source: Annual Reports of the Immigration and Naturalization Service, Department of Justice

Social Security Administration

Office of the Chief Actuary

July 22, 2015
Immigration, Page 11

Table 3.3: Legal Immigration Limits for Fiscal Years Beginning 1995

Unadjusted 

Limit

1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

Family 

Sponsored 

Preference

226,000 to 

480,000 1 253,721 311,819 226,000 226,000 226,000 294,601 226,000 226,000 226,000 226,000 226,000 226,000 226,000 226,000 226,000 226,000 226,000 226,000 226,000

Immediate 

Relatives of 

U.S. Citizens Not Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited 

Not 

Limited 

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited Not Limited

Employment 

Based 140,000 2 146,503 140,000 140,000 140,000 160,906 142,299 192,074 142,632 171,532 204,422 148,449 143,949 147,148 162,704 140,000 150,657 140,000 144,951 158,466

Diversity 55,000 3 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 55,000 50,000

Refugees Set Annually 111,000 90,000 78,000 83,000 91,000 90,000 80,000 70,000 70,000 70,000 70,000 70,000 70,000 80,000 80,000 80,000 80,000 76,000 70,000

Asylees Not Limited 4 10,000 10,000 10,000 10,000 10,000 10,000 10,000 10,000 10,000 10,000

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited

Not 

Limited Not Limited

1 The family preference limit is given as a range because it is equal to the larger of: 226,000 or 480,000 minus the previous 

 year's immediate relatives of U.S. citizens minus certain other small categories of children minus certain categories of aliens

 paroled into the U.S. in the second preceding fiscal year plus unused employment preferences from the previous year.

2 The employment-based preference can be higher than 140,000 if certain other preferences go unused in the previous year.

3

 The Diversity category includes those immigrating through the Nicaraguan Adjustment and Central American Relief Act (NACARA).

4

 The REAL ID Act of 2005 eliminated the numerical limit for Asylees.

Sources:

Family sponsored, Employment based, and Diversity: Table A1 of 

http://www.dhs.gov/sites/default/files/publications/ois_lpr_fr_2013.pdf

Immediate Relatives: all "not limited" unless legislation changes

Refugees: Table 1 of

http://www.dhs.gov/sites/default/files/publications/ois_rfa_fr_2013.pdf

Asylees: Historical years: text on page 6 of 

http://www.dhs.gov/xlibrary/assets/statistics/yearbook/2003/2003Yearbook.pdf

Social Security Administration

Office of the Chief Actuary

July 22, 2015

Limit for Fiscal Year
Immigration, Page 12

Table 3.4: Legal Immigrants Admitted to the United States: Fiscal Years Beginning 1985

(in thousands)

Reflecting Revised Categories in the 1990 Immigration Act, Subject to limitation under the Overall Flexible Cap

Fiscal Year IRCA1

Total non 

IRCA2

Family 

Sponsored

Employment 

Based

Immediate 

Relatives

Refugees & 

Asylees Diversity

Other Specially 

Legislated Immigrants

1985 — 570 213 53 204 95 — 4

1986 — 602 213 57 223 104 — 4

1987 — 602 212 58 219 92 3 19

1988 — 643 201 59 219 82 6 76

1989 479 612 217 58 218 84 7 28

1990 880 656 215 58 232 97 29 25

1991 1,123 704 216 60 237 139 22 30

1992 163 811 213 116 235 117 89 40

1993 24 880 227 147 255 127 89 35

1994 6 798 212 123 250 121 75 17

1995 4 716 238 85 220 115 48 10

1996 — 916 294 117 300 128 58 17

1997 — 798 213 90 321 112 49 12

1998 — 653 191 77 283 52 45 4

1999 — 645 217 57 258 43 48 24

2000 — 841 235 107 346 63 51 39

2001 — 1,059 232 179 440 108 42 59

2002 — 1,059 187 174 484 126 43 46

2003 — 704 159 82 331 45 46 41

2004 — 958 214 155 418 71 50 49

2005 — 1,122 213 247 436 143 46 37

2006 — 1,266 222 159 580 216 44 44

2007 — 1,052 195 162 495 136 42 23

2008 — 1,107 228 165 488 166 42 18

2009 — 1,131 212 141 536 177 48 17

2010 — 1,043 215 148 476 136 50 17

2011 — 1,062 235 139 453 168 50 16

2012 — 1,032 202 144 479 151 40 16

2013 — 991 210 161 439 120 46 14

1

 This category includes those aliens admitted under the Immigration Reform and Control Act of 1986.

2

 Comprehensive immigration legislation increased total immigration under an overall flexible cap of 675,000 immigrants

 beginning in fiscal year 1995, preceded by a 700,000 level during fiscal years 1992 through 1994. 

Source: Table 6 of Annual Reports of the Office of Immigration Statistics, Department of Homeland Security

Social Security Administration

Office of the Chief Actuary

July 22, 2015