Number range CHAPTER![](media/image1.wmf)

**2005 NEW YORK CITY HOUSING AND VACANCY SURVEY**

**SAMPLE DESIGN, ESTIMATION PROCEDURE AND ACCURACY STATEMENT**

**I. SAMPLE DESIGN**

> The City of New York is required by law periodically to conduct a
> survey to determine if rent regulations should be continued. A primary
> tool in this decision is the *\"vacant available for rent\"* rate,
> which is defined as the ratio of the vacant available for rent units
> to the total number of renter occupied and vacant available for rent
> units for the entire city. The New York City Housing and Vacancy
> Survey (NYCHVS) measures rental and homeowner vacancy rates, as well
> as various household and person characteristics. The design requires
> the standard error of the esti­mate of the vacant available for rent
> rate for the entire city be no more than one-fourth of 1 percent, if
> the actual rate was 3 percent.
>
> **A. Sampling Frames**
>
> The 2005 NYCHVS sample consists of housing units selected from the
> following three sampling frames:

1.  Housing units included in the 2000 Census

2.  Housing units constructed since the 2000 Census

3.  Housing units in structures owned by New York City (IN REM). These
    types of housing units were oversampled to ensure a large enough
    sample for analysis of this subuniverse. Note that these housing
    units are also part of the 2000 Census frame.

    The NYCHVS sample includes only housing units. The principal
    exclusions were living quarters classified as:

-   Transient hotels,

-   Commercial and mission lodging houses,

-   Inmate living quarters in institutions,

-   Quarters for the military on military installations, and

-   Other large group quarters not meeting the definition of a housing
    unit.

    Also, generally excluded were housing units in special places. These
    included housing units located on the grounds of institutions (both
    civilian and military). Residential hotels and motels, however, were
    included in the survey.

    **B. Sample Selection**

    Within each NYCHVS sampling frame, we selected clusters (groups of
    housing units) of generally four housing units, with the exception
    of IN REM units where we selected clusters of size five. For all
    frames except the IN REM frame, the housing units were consecutive
    units. For the IN REM frame, we selected a systematic sample of
    housing units within each sample building.

    1\. [Housing Units Included in the 2000 Census]{.underline}

    Within this frame, we sorted housing units by (a) borough, (b)
    sub-borough, (c) percent renter occupied in the block, (d)
    tract, (e) block number, (f) basic street address, and (g) unit
    designation. We selected a systematic sample of housing units across
    all boroughs. This frame included IN REM units.

    2\. [Housing Units Constructed Since the 2000 Census]{.underline}

    We selected units in this frame from Certificates of Occupancy (C of
    Os) issued between January 2000 and November 2004. We dropped all
    housing units that were also on the 2000 census frame from this
    sample. We sorted the housing units by borough and date (i.e., year
    and month) of issue and selected a systematic sample of housing
    units within each borough. We listed each structure that contained a
    sample housing unit and then identified the designated sample unit
    in the order in which the unit appeared on these listings.

    3\. [Housing Units in Structures Owned by New York City (IN
    REM)]{.underline}

    This frame consisted of units in structures owned by New York City
    as of November 2004. The City owned these units because the owner
    failed to pay the real estate tax and/or other charges on the
    property. We selected a probability proportional to size sample of
    in rem buildings first, then selected sample units within buildings.
    In this procedure, each building is assigned a probability of
    selection based on the expected number of housing units in the
    building. This probability is in direct proportion to this expected
    number of units. Thus, a building with 8 units has twice the
    probability of selection as a building that has 4 units. Buildings
    are sampled using these probabilities.

    First, we sorted the buildings by:

    \(1\) Borough, and

    \(2\) Size of the Building (number of units)

    We selected a systematic sample of buildings, then, after listing
    the individual units in each building, we selected a systematic
    sample of units within each sample building.

    **C. Sample Size**

    The total number of sample housing units selected for the 2005
    NYCHVS was 18,516. The table below provides the total number of
    sampled housing units by borough.

+-----------------------------------+----------------------------------+
| Borough                           | Number of Housing Units          |
+-----------------------------------+----------------------------------+
| Bronx                             | 2,826                            |
|                                   |                                  |
| Brooklyn                          | 5,241                            |
|                                   |                                  |
| Manhattan                         | 4,949                            |
|                                   |                                  |
| Queens                            | 4,540                            |
|                                   |                                  |
| Staten Island                     | 960                              |
+-----------------------------------+----------------------------------+
| Total                             | 18,516                           |
+-----------------------------------+----------------------------------+

Of these housing units, 726 interviews were not obtained because, for
occupied housing units, the occupants

\- refused to be interviewed,

\- were not at home after repeated visits,

\- or were unavailable for some other reason.

For vacant units, an interview wasn\'t obtained if no informed
respondent could be found after repeated visits. These 726 noninterviews
are known as type-A noninterviews. There were an additional 956 units,
known as type-C noninterviews, that were not interviewed because they no
longer exist or are uninhabitable. This classification produced a 96
percent overall response rate (18,516-956-726)/(18,516-956) =
(16,834/17,560).

The sample housing units were visited between January and June 2005 by
field representatives (FRs) hired and trained for this task. The FRs
visited each sample address and completed a questionnaire for both
occupied and vacant units. In addition, for evaluation purposes, the
occupancy status of all vacant units and a sample of occupied units was
independently determined in a reinterview. An independent third
interview reconciled any differences.

**II. ESTIMATION PROCEDURE**

To compute estimates of housing unit and person characteristics based on
the data we collected for the 2005 NYCHVS, we calculated sample weights
for each housing unit and person record. The final weight for each
housing unit equals the product of the following weight and adjustments:

1\. Base Weight

We determined a base weight as the reciprocal of the probability of
selecting the unit. Because IN REM sample units and a few census sample
units were eligible for selection from both the 2000 Census and the IN
REM frames, we adjusted the basic weights of these units to reflect the
fact that they had multiple chances of selection.

2\. Nonresponse Adjustment

We adjusted the base weight of each interviewed housing unit to account
for the 726 eligible units that did not respond (type-A noninterviews).

3\. Ratio Adjustments

We adjusted the sampling weights using a three-stage housing unit ratio
estimation procedure to do the following:

● to account for known sampling variability in the 2000 Census frame,

● to account for known sampling variability in the IN REM frame,

● to bring the sample estimates of housing units into close agreement
with estimates derived from independent sources, and

● to account for housing unit undercoverage.

We used the same procedure to determine weights for estimating person
characteristics, but added a ratio adjustment to adjust for person
undercoverage within households.

A. [Nonresponse Adjustment]{.underline}

We applied a noninterview adjustment factor to all interviewed housing
units to account for type-A noninterviews using a factor equal to the
following ratio:

func{\~\~\~\~\~{(weighted\~count\~of\~interviewed\~units)\~+\~(weighted\~count\~of\~Type\~A\~noninterviews)}over{(weighted\~count\~of\~interviewed\~units)}}

We computed the factor separately for old construction and new
construction housing units as follows:

[Old Construction]{.underline}

1\. For sample housing units selected from the 2000 Census frame, we
computed the noninterview adjustment factor separately by borough using
the characteristics below. We used 2002 NYCHVS data where available to
determine the tenure and characteristics cell of a unit. If the 2002
NYCHVS data were not available, we used 2005 NYCHVS data.

a\. For renter-occupied units HUs, we used

[Monthly rent]{.underline}

-   \< \$100

-   \$100-\$199

-   \$200-\$299

-   \$300-\$399

-   \$400-\$499

-   \$500-\$599

-   \$600-\$699

-   \$700-\$999

-   \$1,000

    [Number of Rooms]{.underline}

-   1, 2, 3, 4+, or

-   1-2, 3, 4, 5+ or

-   1-3, 4, 5, 6+

    b\. For owner-occupied units HUs, we used

    [Value]{.underline}

-   \< \$25,000

-   \$25,000-\$49,999

-   \$50,000-\$74,999

-   \$75,000-\$99,999

-   \$100,000-\$149,999

-   \$150,000-\$199,999

-   \$200,000-\$249,999

-   \$250,000-\$299,999

-   \$300,000-\$399,999

-   \$400,000-\$499,999

-   \$500,000

    [Number of Rooms]{.underline}

-   1-4, 5, 6, 7+ or

-   1-3, 4, 5, 6+ or

-   1-3, 4, 5-6, 7+ or

-   1-4, 5, 6, 7+ or

-   1-5, 6, 7, 8+ or

-   1-5, 6-7, 8, 9+

    c\. For vacant units, we used

    [Vacancy status]{.underline}

-   renter occupied/vacant for rent,

-   owner occupied/vacant for sale,

-   vacant/unavailable or vacancy status unknown.

    2\. We computed the factor for IN REM units separately by borough.

    [New Construction]{.underline}

    For new construction units, we computed the factor separately using
    segment number range and borough.

    B. [Ratio Estimate Factors]{.underline}

    For each ratio estimation procedure, we computed factors for ratio
    estimate cells and applied the factors to the appropriate units in
    the corresponding cell. The factors were equal to the following
    ratio:

    func{\~\~\~\~\~{Independent\~Estimate\~of
    \~the\~Number\~of\~HUs\~(persons)\~for\~the\~cell} over
    {NYCHVS\~Sample\~Estimate\~of\~the\~Number\~of\~HUs\~(persons)\~for\~the\~cell}}The
    denominators of the ratios equals the sum of the weights of housing
    units (or persons) with all previous factors applied.

    1\. [2000 Census Ratio Estimate Factor]{.underline}

    This procedure adjusted for differences between the 2000 Census
    counts and the corresponding sample counts. We adjusted the weights
    of all NYCHVS sample units selected from the 2000 Census frame. We
    computed the factors separately by borough using the following 2000
    Census characteristics:

-   For renter-occupied housing units, we used

    \(a\) *Subborough* (Bronx(10), Brooklyn (18), Manhattan (10), Queens
    (14), Staten Island (3))

    \(b\) *Number of Persons in the Housing Units* (1, 2, 3-4, 5 or
    more)

    \(c\) *Race of the Householder* (White, Black, All Remaining Races)

-   For owner-occupied housing units, we used

    \(a\) *Subborough* (Bronx(10), Brooklyn (18), Manhattan (10), Queens
    (14), Staten Island (3))

    \(b\) *Number of Persons in the Housing Units* (1, 2, 3-4, 5 or
    more)

-   For vacant housing units, we used *vacancy status* (vacant for rent;
    vacant for sale; rented/sold; seasonal; migrant; other.)

    2\. [IN REM Ratio Estimate Factor]{.underline}

    This procedure adjusts for known sampling variability in the IN REM
    sample selection. We adjusted the weights of all sample units
    selected from the IN REM frame by borough (5 cells). We used the
    total number of units in each borough in the IN REM frame as control
    totals.

    3\. [2005 Housing Unit Ratio Estimate Factor]{.underline}

    This procedure adjusted the 2005 NYCHVS sample estimate for housing
    unit undercoverage by controlling the sample estimate to independent
    estimates of 2005 total housing units. The control totals were
    derived from 2000 Census housing unit totals. We applied this ratio
    estimation procedure to all interviewed housing units. We calculated
    the ratio estimate factor for each of the boroughs (5 cells)**.**
    The independent estimates were 2000 Census counts of the total
    number of housing units in each of the boroughs at the time of the
    2005 survey**.**

    4\. [2005 Person Ratio Estimate Factor]{.underline}

    This additional adjustment accounted for sampling variability and
    known coverage deficiencies for persons within interviewed
    households. This ratio estimation assumes that reference persons,
    spouses or unmarried partners are always picked up during the
    interview and only persons other than a reference person, spouse or
    unmarried partner could be missed in households. We computed this
    factor within each borough by age, race and sex (80 cells).

-   The numerator of the ratio equaled the independent estimate of 2005
    total persons for the cell minus the NYCHVS sample estimate of
    reference persons and spouses or unmarried partners. The independent
    estimates were projected based on 2000 Census person totals.

-   The denominator of the ratio equaled the NYCHVS sample estimate of
    persons other than reference persons, spouses or unmarried partners
    for the cell. The person ratio estimate factor was applied only to
    the persons other than reference persons, spouses, or unmarried
    partners.

    The ratio estimation procedures, as well as the overall estimation
    procedure, reduced the sampling error for most statistics below what
    would have been obtained by simply weighting the sample by the base
    weight.

    **III. SAMPLING AND NONSAMPLING ERRORS**

    Since the statistics produced from this survey are estimates derived
    from a sample, they will differ from the "true values" being
    estimated. There are two types of errors which cause estimates based
    on a sample survey to differ from the true value - sampling error
    and nonsampling error.

    A. [Nonsampling Errors]{.underline}

    If every housing unit in New York City were interviewed, the
    estimates of housing unit characteristics would still differ from
    the true value (for example, the median contract rent). In this
    instance, the difference is due solely to nonsampling errors. We
    attribute nonsampling errors in sample surveys to many sources:

    ● deficiencies in the sampling frame (i.e., not all housing units
    are covered),

    ● inability to pick up all persons within sample households,

    ● inability to obtain information about all cases in the sample,

    ● definitional difficulties,

    ● differences in the interpretation of questions,

    ● inability or unwillingness to provide correct information on the
    part of the respondents, and

    ● mistakes in recording, coding or keying the data obtained.

    There are also other errors of collection, response, processing,
    coverage, and estimation for missing data.

    In the 2005 NYCHVS, we missed about five percent of the housing
    units in the five boroughs covered by the survey. Overall, we missed
    about eight percent of the people in sample households. This
    within-household undercoverage varied by age, race, sex, and
    borough. It ranged from about a 27-percent overcoverage of White
    females between 15-24 in Manhattan to a 60**-**percent undercoverage
    of Other males between 15-24 in Staten Island. The following table
    gives the undercoverage of the various race-sex groups for the city
    as a whole:

  ------------------------------------------- ---------------------------
  Race-Sex Group                              Undercoverage

  White & Other Females                       6%

  White & Other Males                         9%

  African American Females                    5%

  African American Males                      11%
  ------------------------------------------- ---------------------------

We adjusted for this undercoverage through the housing unit and person
ratio estimate factors previously described. Measures of other errors
for this survey are not available. However, we believe some of the
important response and most of the operational errors were detected and
corrected during the Bureau\'s review of the data for reasonableness and
consistency.

B. [Sampling Errors]{.underline}

Sampling error is a measure of how estimates from a sample vary from the
actual value. NOTE: By the term \"actual value\" we mean the value we
would have gotten had all housing units been interviewed, under the same
conditions, rather than only a sample.

The formulas in Tables 1 through 6, citywide and for each borough which
can be found toward the end of this document, allow you to compute a
range of error such that there is a known probability of being correct
if you say the actual value is within the range. The error formu­las are
approxi­mations to the errors. They indicate the order of magni­tude of
the errors rather than the actual errors for any specif­ic
char­ac­teris­tic. To construct the range, add and subtract the error
computed from the formulas to the esti­mate. A table of the Standard
Errors of the Estimates for selected NYCHVS items is posted at the
Census Bureau's website at
[http://www.census.gov/hhes/www/housing/nychvs/2005/se_contract.pdf]{.underline}.

The letter "A" in the formula represents the weighted sample esti­mate
you derive from the file.

The letter \"Z\" determines the probabili­ty the actual value is within
the range you compute. The larger the value of Z, the larger the range,
and the higher the odds the actual value will be in the range. The
following values of Z are most commonly used.

  --------------- -------------------------------------------------------
  Value of Z      Meaning

  1.00            There is a 67-percent chance you\'ll be correct if you
                  say the ac­tual value is in the range you com­p­ute.

  1.64            There is a 90-percent chance you\'ll be correct if you
                  say the ac­tual value is in the range you com­p­ute.

  1.96            There is a 95-percent chance you\'ll be correct if you
                  say the ac­tual value is in the range you com­p­ute.

  2.58            There is a 99-percent chance you\'ll be correct if you
                  say the ac­tual value is in the range you com­p­ute.
  --------------- -------------------------------------------------------

Note that if Z = 1.00, the formula computes the standard error. Ranges
of 90 and 95-percent are commonly used. The range of error is also
referred to as the confidence inter­val since there is a certain level of
confidence the actual value is within the inter­val. You can compute a
standard error and confidence interval for data from the HVS that are
total numbers, percents, differences, medians, or means using formulas
from Tables 1-6 as shown in the following examples.

Sets of standard errors have been computed for New York City as a whole
and for each of the five boroughs. Table 1 contains the set for New York
City and Tables 2 through 6 for each of the boroughs. The tables are
divided into two major sections. The upper portion contains three
formulas that apply to housing units. The lower portion contains seven
formulas that apply to persons. Tables 7A and 7B contain a description
of which formula to use for estimates pertaining to housing units. Table
7A specifically pertains to the second of the three formulas. Table 7B
specifically pertains to the third of the three formulas. The first
formula is used for any item not listed in either Table 7A or 7B. The
first column in Tables 7A and 7B lists the characteristic for which the
tables are to be applied. The second column lists the applicable
subgroups (e.g. total occupied, vacant for rent, etc). If the estimate
of interest matches to both the first and second column

of either table, use the corresponding formula. If no match is found,
use the first formula.

1\. [Totals]{.underline}

According to the 2005 HVS, there are 17,759 vacant-for-rent units in
Brooklyn. To compute a 90-percent confidence interval, you would use the
first formula in Table 3 and you would compute the error as follows:

func{1.64\~x\~sqrt{(264.79\~x\~17,759)\~-\~(0.000253\~x\~17,759\^2)}\~=\~3,526}func{Z\~x\~sqrt{(264.79\~x\~A)\~-\~(0.000253\~x\~A\^2)}}

Thus there is a 90-percent chance you\'ll be correct if you con­clude the
actual number of vacant-for-rent units in Brooklyn is 17,759 plus or
minus 3,526 or in the range 14,233 to 21,285.

If the estimate involves two characteristics from Tables 1 through 6,
use the formula with the larger first number under the square root.

2\. [Percents]{.underline}

The formula (not shown in a table) for computing the error of any
percent derived from the data is the following:

func{Z\~x\~Y\~x\~sqrt{{264.79\~x\~P\~x\~(100-P)} over B}}where:

Z: defines the confidence the range will include the actual value,

Y: is the number from the last column of Tables 1 through 6 (chosen
based on the characteristics represented in the numerator and
denominator),

P: is the percent you calculate, and

B: is the denominator of the percent.

For example, there are 636,271 occupied home owner conventional housing
units in New York City and 135,187, or 21.25 percent, were built between
1947 and 1969. Using Table 1 for New York City, together with Tables 7A
and 7B, you choose the value of Y = 1 because the characteristic is not
included in 7A or 7B. (While year-built is in 7B, the subgroup owner
occupied units is not). To compute a 90-percent confidence interval you
would plug the following numbers into the above formula:

func{1.64\~x\~1.000\~x\~sqrt{{264.79\~x\~21.25\~x\~78.75} over
{636,271}}\~\~=\~1.4}

Thus, if you say that the actual percentage of owners in buildings built
between 1947 and 1969 is between 19.9 percent and 22.6 percent, there is
a 90-percent chance you\'ll be correct.

3\. [Differences]{.underline}

People often ask whether two numbers are actually different. If the
range of error for the difference doesn\'t include zero, the numbers are
different. As a general rule, if the confidence intervals don\'t
overlap, they\'re different. To compute the range of error of the
difference use the following formula:

func{\~\~\~\~\~sqrt{(\\error\\ on\~first\~number)\^2\~+\~(\\error\\
on\~second\~number)\^2}}

This formula is quite accurate for (a) the differ­ence be­tween estimates
of the same item in two different areas or (b) the differ­ence between
separate and uncorrela­ted items in the same area. If there is a high
positive correlation between the two items, the formula will
overesti­mate the error. If there is a high negative correla­tion, the
formula will underestimate the error. The follow­ing illustration shows
how to compute the error of a difference.

There are 10,832 vacant-for-rent units in New York City with 3 to 5
units in the building and 4,287 vacant-for-rent units with 6 to 9 units
in the building. The respective errors for a 90-percent confi­dence
inter­val are 2,773 and 1,746. The error for a 90­-percent confidence
interval for the 6,545 dif­ference is the follow­ing:

func{sqrt{(2,773)\^2\~+\~(1,746)\^2}\~=\~3,277}

Thus, there is a 90-percent chance you\'ll be correct if you say the
actual difference between vacant-for-rent units in 3 to 5 unit buildings
vs. 6 to 9 unit buildings in New York City is between 3,268 and 9,822.

4\. [Medians]{.underline}

The median is the value 50-percent of the way through the distribution.
Thus, 50-percent of the total falls below and 50-percent falls above the
median. Note that the median presented in this example is the true
median (i.e., computed by SAS) not an approximation. You can construct a
confidence interval around the median by computing the standard error on
a 50-percent characteristic and then translating that into an interval
for the characteristic.

a\. Using the error formula for percents, above, compute the error of
50-percent. The total number of housing units from the distribution is
the denominator in the formula. Subtract the \"not applicable\" category
from the total.

b\. Calculate the confidence interval for the true median by adding and
subtracting the width of the interval containing the median times the
standard error on the 50-percent characteristic divided by the
proportion of units in the interval containing the median, to the
median.

The probability you will be correct if you conclude that the actual
median is within the interval depends on the value of Z in the error of
percent formula. The following example shows how to compute a 90-percent
confidence interval.

For example, the median value for all occupied housing units in New York
City is \$400,000. The number of occupied housing units in the
distribution of value of units is presented below.

Distribution of Value of Units

  -------------------------------------------------------------------------
  Value                   Number of HUs     Percent         Cumulative
                                                            Percent
  ----------------------- ----------------- --------------- ---------------
  Less Than \$25,000      38,216            3.78            3.8

  \$25,000-\$49,999       8,786             0.87            4.7

  \$50,000-\$74,999       18,040            1.79            6.4

  \$75,000-\$99,999       16,336            1.62            8.1

  \$100,000-\$149,999     35,868            3.55            11.6

  \$150,000-\$199,999     41,293            4.09            15.7

  \$200,000-\$249,999     60,109            5.95            21.6

  \$250,000-\$299,999     61,024            6.04            27.7

  \$300,000-\$349,999     95,929            9.49            37.2

  \$350,000-\$399,999     96,176            9.52            46.7

  \$400,000-\$499,999     168,557           16.68           63.4

  \$500,000-\$599,999     125,326           12.40           75.8

  \$600,000-\$699,999     76,440            7.57            83.3

  \$700,000-\$799,999     43,541            4.31            87.7

  \$800,000-\$999,999     47,496            4.70            92.4

  \$1,000,000 or more     77,233            7.64            100.0

  Not Applicable          2,027,626                         

  TOTAL                   3,037,996                         
  -------------------------------------------------------------------------

The error on a 50-percent characteristic based on 1,010,370 (3,037,996
minus the \"not applicable\" number) housing units is calculated as
illustrated below. *Since the median value is the endpoint of an
interval, calculate the average of the errors for the interval
containing the median and the interval above the interval containing the
median.*

func{\~\~\~\~\~\~\~\~\~\~1.64\~x\~1.0000\~x\~sqrt{{264.79\~x\~50\~x\~50}
over
{1,010,370}}\~\~=\~1.33}func{\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~{(499,999.5\`-\`399,999.5)}\`x\`{{1.33}
over{ 16.68}}\~=\~7,974 }

func{\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~(399,999.5\`-\`349,999.5)\`x\`{1.33}
over { 9.52}\~=\~6,985 }

func{\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~\~{7,974\~+\~6,985} over {
2}\~=\~7,479 }

where:

● 499,999.5-399,999.5 is the width of the interval that contains the
median and 399,999.5-349,999.5 is the width of the interval above the
interval containing the median.

● 1.33 is the error for a 90-percent confidence interval for the
50-percent characteristic

● 16.68 is the percent of cases that fall in the interval containing the
median and 9.52 is the percent of cases that fall in the interval above
the interval containing the median.

The 90-percent confidence interval for the median (\$400,000) is:

\$400,000 ± \$7,479

Thus, there is a 90-percent chance that you will be correct if you
conclude that the actual median value for all occupied housing units in
New York City is between \$392,521 and \$407,479.

5\. [Means]{.underline}

The mean and the median usually differ. The mean is usually higher
because it is influenced more heavily than the median by very large
values. Use the following formula to estimate the error of the mean:

func{Z\~x\~Y\~x\~ SQRT { LEFT \[{sum from {i\~=\~1} to {n}\~{p SUB{i} x
SUB{i} SUP {2}}\~-\~{(sum from {i\~=\~1} to {n}\~{p\_{i}\~x_i})}}\^2
RIGHT \] over {c}\~x \~264.79}}

where:

Y: is the number from the last column of Tables 1 through 6.

For housing unit characteristics, review Tables 7A and 7B. If both the
characteristic and the subgroup match to any listed in either table, use
the corresponding value for Y (the second listed for a match to Table
7A, the third for a match to Table 7B). If no match is found, use the
first vlaue of Y, that is 1.00.

Z: defines the confidence the range will include the actual value

p~i~: is the proportion of total households or persons from a
distribution in the i^th^ interval

x~i~: is the midpoint of the i^th^ interval (NOTE: The midpoint of the
open-ended interval is 1.5 times the lower limit)

c: is the total number of households or persons in the distribution
(NOTE: Subtract the number of \"not applicable\" from the total to get
c)

n: is the total number of intervals in the distribution

For example, the mean (or average) value of all occupied housing units
in New York City was \$491,756 (compared to a median of \$400,000). The
distribution from which the mean was computed is given below.

  --------------------- ----------------- ------------ -------------------
  Value                 Number of HUs     p~i~         x~i~

  Less Than \$25,000    38,216            .0378        \$12,500

  \$25,000-\$49,999     8,786             .0087        \$37,500

  \$50,000-\$74,999     18,040            .0179        \$62,500

  \$75,000-\$99,999     16,336            .0162        \$87,500

  \$100,000-\$149,999   35,868            .0355        \$125,000

  \$150,000-\$199,999   41,293            .0409        \$175,000

  \$200,000-\$249,999   60,109            .0595        \$225,000

  \$250,000-\$299,999   61,024            .0604        \$275,000

  \$300,000-\$349,999   95,929            .0949        \$325,000

  \$350,000-\$399,999   96,176            .0952        \$375,000

  \$400,000-\$499,999   168,557           .1668        \$450,000

  \$500,000-\$599,999   125,326           .1240        \$550,000

  \$600,000-\$699,999   76,440            .0757        \$650,000

  \$700,000-\$799,999   43,541            .0431        \$750,000

  \$800,000-\$999,999   47,496            .0470        \$900,000

  \$1,000,000 Or More   77,233            .0764        \$1,500,000

  Not Applicable        2,027,626         \-\-\-\--    

  Total                 3,037,996         1.000        
  --------------------- ----------------- ------------ -------------------

Plugging the numbers in the above formula, the error for a 90-percent
confidence interval on the mean income is computed as follows:

func{1.64\~x\~1.000\~x\~SQRT{{370,588,736,985\~-\~{(493,226) SUP 2}}
over {1,010,370}\~x\~264.79}\~=\~\$9,473}

Thus, there is a 90-percent chance of being correct if you say the mean
value of all occupied housing units in New York City was between
\$482,283 and \$501,229.

**Table 1: Errors for New York City**

  -----------------------------------------------------------------------------------------------
                       Publication Estimates                                        Percentages
  -------------------- ------------------------------------------------------------ -------------
                       The error is the larger of:                                  Value of Y
                                                                                    for Percent
                                                                                    Formula

  **Errors on Housing                                                               
  Units**                                                                           

  **Housing Unit       Z\~x\~ SQRT                                                  1.000
  Characteristics Not  {264.79\~x\~A\~-\~.000075\~x\~A\^{2}}\~\\or\~Z\~x\~265       
  Listed in Tables 7A                                                               
  or 7B**                                                                           

  **Housing Unit       Z\~x\~ SQRT                                                  1.324
  Characteristics^1^   {463.92\~x\~A\~-\~.000131\~A\^{2}}\~\\or\~Z\~x\~464          
  Listed in Table 7A**                                                              

  **Housing Unit       Z\~x\~ SQRT                                                  1.539
  Characteristics^2^   {626.87\~x\~A-\~.000176\~x\~A\^{2}}\~\\or\~Z\~x\~627         
  Listed in Table 7B**                                                              

  **Errors on                                                                       
  Persons**                                                                         

  **Characteristics of Z\~x\~ SQRT                                                  1.014
  Persons Not Listed   {273.98\~x\~A\~-\~.000035\~x\~A\^{2}}\~\\or\~Z\~x\~274       
  Below**                                                                           

                       **NOTE: For any of the person characteristics listed below   
                       that are cross-tabbed by Borough and Sub-borough use the     
                       formula for the specific characteristic listed below. Don\'t 
                       use the formulas listed below for cross-tabs of              
                       characteristics of persons listed below {e.g., Age by sex    
                       (males under 25), Age by Race (African Americans under 25),  
                       or sex by race (white females)}. Use the formula above       
                       (Characteristics of Persons Not Listed Below).**             

  **Whites and other   Z\~x\~ SQRT                                                  1.575
  Races and            {661.53\~x\~A\~-\~.000109\~x\~A\^{2}}\~\\or\~Z\~x\~662       
  Ethnicity**                                                                       

  **Males**            Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.000176\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Females**          Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.000159\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Persons under 25   Z\~x\~ SQRT                                                  1.398
  yrs. old**           {521.06\~x\~A\~-\~.000066\~x\~A\^{2}}\~\\or\~Z\~x\~521       

  **African            Z\~x\~ SQRT                                                  2.296
  Americans**          {1,405.55\~x\~A\~-\~.000757\~x\~A\^{2}}\~\\or\~Z\~x\~1,406   

  **Borough and        x\~ SQRT                                                     2.296
  Sub-borough**^3^     {1,405.55\~x\~A\~-\~.000178\~x\~A\^{2}}\~\\or\~Z\~x\~1,406   
  -----------------------------------------------------------------------------------------------

^1^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7A. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^2^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7B. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^3^ Exclude total population in households. Use the formula for
"Characteristics of Persons Not Listed Below" for these person
characteristics.

**Table 2: Errors for Bronx**

  -----------------------------------------------------------------------------------------------
                       Publication Estimates                                        Percentages
  -------------------- ------------------------------------------------------------ -------------
                       The error is the larger of:                                  Value of Y
                                                                                    for Percent
                                                                                    Formula

  **Errors on Housing                                                               
  Units**                                                                           

  **Housing Unit       Z\~x\~ SQRT                                                  1.000
  Characteristics Not  {264.79\~x\~A\~-\~.000490\~x\~A\^{2}}\~\\or\~Z\~x\~265       
  Listed in Tables 7A                                                               
  or 7B**                                                                           

  **Housing Unit       Z\~x\~ SQRT                                                  1.324
  Characteristics^1^   {463.92\~x\~A\~-\~.000858\~A\^{2}}\~\\or\~Z\~x\~464          
  Listed in Table 7A**                                                              

  **Housing Unit       Z\~x\~ SQRT                                                  1.539
  Characteristics^2^   {626.87\~x\~A-\~.001159\~x\~A\^{2}}\~\\or\~Z\~x\~627         
  Listed in Table 7B**                                                              

  **Errors on                                                                       
  Persons**                                                                         

  **Characteristics of Z\~x\~ SQRT                                                  1.014
  Persons Not Listed   {273.98\~x\~A\~-\~.000208\~x\~A\^{2}}\~\\or\~Z\~x\~274       
  Below**                                                                           

                       **NOTE: For any of the person characteristics listed below   
                       that are cross-tabbed by Borough and Sub-borough use the     
                       formula for the specific characteristic listed below. Don\'t 
                       use the formulas listed below for cross-tabs of              
                       characteristics of persons listed below {e.g., Age by sex    
                       (males under 25), Age by Race (African Americans under 25),  
                       or sex by race (white females)}. Use the formula above       
                       (Characteristics of Persons Not Listed Below).**             

  **Whites and other   Z\~x\~ SQRT                                                  1.575
  Races and            {661.53\~x\~A\~-\~.000725\~x\~A\^{2}}\~\\or\~Z\~x\~662       
  Ethnicity**                                                                       

  **Males**            Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.001082\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Females**          Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.000939\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Persons under 25   Z\~x\~ SQRT                                                  1.398
  yrs. old**           {521.06\~x\~A\~-\~.000396\~x\~A\^{2}}\~\\or\~Z\~x\~521       

  **African            Z\~x\~ SQRT                                                  2.296
  Americans**          {1,405.55\~x\~A\~-.003488\~x\~A\^{2}}\~\\or\~Z\~x\~1, 406    

  **Sub-borough and    Z\~x\~ SQRT                                                  2.296
  Borough** ^3^        {1,405.55\~x\~A\~-\~.001068\~x\~A\^{2}}\~\\or\~Z\~x\~1,406   
  -----------------------------------------------------------------------------------------------

^1^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7A. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^2^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7B. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^3^ Exclude total population in households. Use the formula for
"Characteristics of Persons Not Listed Below" for these person
characteristics.

**Table 3: Errors for Brooklyn**

  -----------------------------------------------------------------------------------------------
                       Publication Estimates                                        Percentages
  -------------------- ------------------------------------------------------------ -------------
                       The error is the larger of:                                  Value of Y
                                                                                    for Percent
                                                                                    Formula

  **Errors on Housing                                                               
  Units**                                                                           

  Housing Unit         Z\~x\~ SQRT                                                  1.000
  Characteristics Not  {264.79\~x\~A\~-\~.000253\~x\~A\^{2}}\~\\or\~Z\~x\~265       
  Listed in Tables 7A                                                               
  or 7B                                                                             

  **Housing Unit       Z\~x\~ SQRT                                                  1.324
  Characteristics^1^   {463.92\~x\~A\~-\~.000442\~A\^{2}}\~\\or\~Z\~x\~464          
  Listed in Table 7A**                                                              

  **Housing Unit       Z\~x\~ SQRT                                                  1.539
  Characteristics^2^   {626.87\~x\~A-\~.000598\~x\~A\^{2}}\~\\or\~Z\~x\~627         
  Listed in Table 7B**                                                              

  **Errors on                                                                       
  Persons**                                                                         

  **Characteristics of Z\~x\~ SQRT                                                  1.014
  Persons Not Listed   {273.98\~x\~A\~-\~.000113\~x\~A\^{2}}\~\\or\~Z\~x\~274       
  Below**                                                                           

                       **NOTE: For any of the person characteristics listed below   
                       that are cross-tabbed by Borough and Sub-borough use the     
                       formula for the specific characteristic listed below. Don\'t 
                       use the formulas listed below for cross-tabs of              
                       characteristics of persons listed below {e.g., Age by sex    
                       (males under 25), Age by Race (African Americans under 25),  
                       or sex by race (white females)}. Use the formula above       
                       (Characteristics of Persons Not Listed Below).**             

  **Whites and other   Z\~x\~ SQRT                                                  1.575
  Races and            {661.53\~x\~A\~-\~.000406\~x\~A\^{2}}\~\\or\~Z\~x\~662       
  Ethnicity**                                                                       

  **Males**            Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.000579\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Females**          Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.000514\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Persons under 25   Z\~x\~ SQRT                                                  1.398
  yrs. old**           {521.06\~x\~A\~-\~.000214\~x\~A\^{2}}\~\\or\~Z\~x\~521       

  **African            Z\~x\~ SQRT                                                  2.296
  Americans**          {1,405.55\~x\~A\~-\~.001752\~x\~A\^{2}}\~\\or\~Z\~x\~1,406   

  **Sub-borough and    Z\~x\~ SQRT                                                  2.296
  Borough** ^3^        {1,405.55\~x\~A\~-\~.000578\~x\~A\^{2}}\~\\or\~Z\~x\~1,406   
  -----------------------------------------------------------------------------------------------

^1^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7A. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^2^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7B. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^3^ Exclude total population in households. Use the formula for
"Characteristics of Persons Not Listed Below" for these person
characteristics.

**Table 4: Errors for Manhattan**

  -----------------------------------------------------------------------------------------------
                       Publication Estimates                                        Percentages
  -------------------- ------------------------------------------------------------ -------------
                       The error is the larger of:                                  Value of Y
                                                                                    for Percent
                                                                                    Formula

  **Errors on Housing                                                               
  Units**                                                                           

  **Housing Unit       Z\~x\~ SQRT                                                  1.000
  Characteristics Not  {264.79\~x\~A\~-\~.000301\~x\~A\^{2}}\~\\or\~Z\~x\~265       
  Listed in Tables 7A                                                               
  or 7B**                                                                           

  **Housing Unit       Z\~x\~ SQRT                                                  1.324
  Characteristics^1^   {463.92\~x\~A\~-\~.000527\~A\^{2}}\~\\or\~Z\~x\~464          
  Listed in Table 7A**                                                              

  **Housing Unit       Z\~x\~ SQRT                                                  1.539
  Characteristics^2^   {626.87\~x\~A-\~.000712\~x\~A\^{2}}\~\\or\~Z\~x\~627         
  Listed in Table 7B**                                                              

  **Errors on                                                                       
  Persons**                                                                         

  **Characteristics of Z\~x\~ SQRT                                                  1.014
  Persons Not Listed   {273.98\~A\~-\~.000183x\~A\^{2}}\~\\or\~Z\~x\~274            
  Below**                                                                           

                       **NOTE: For any of the person characteristics listed below   
                       that are cross-tabbed by Borough and Sub-borough use the     
                       formula for the specific characteristic listed below. Don\'t 
                       use the formulas listed below for cross-tabs of              
                       characteristics of persons listed below {e.g., Age by sex    
                       (males under 25), Age by Race (African Americans under 25),  
                       or sex by race (white females)}. Use the formula above       
                       (Characteristics of Persons Not Listed Below).**             

  **Whites and other   Z\~x\~ SQRT                                                  1.575
  Races and            {661.53\~x\~A\~-\~.000504\~x\~A\^{2}}\~\\or\~Z\~x\~662       
  Ethnicity**                                                                       

  **Males**            Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.000929\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Females**          Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.000839\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Persons under 25   \~Z\~x\~ SQRT                                                1.398
  yrs. old**           {521.06\~x\~A\~-\~.000347\~x\~A\^{2}}\~\\or\~Z\~x\~521       

  **African            Z\~x\~ SQRT                                                  2.296
  Americans**          {1,405.55\~A\~-\~.007493\~x\~A\^{2}}\~\\or\~Z\~x\~1,406      

  **Sub-borough and    Z\~x\~ SQRT                                                  2.296
  Borough** ^3^        {1,405.55\~x\~A\~-\~.000937\~x\~A\^{2}}\~\\or\~Z\~x\~1,406   
  -----------------------------------------------------------------------------------------------

^1^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7A. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^2^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7B. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^3^ Exclude total population in households. Use the formula for
"Characteristics of Persons Not Listed Below" for these person
characteristics.

**Table 5: Errors for Queens**

  ---------------------------------------------------------------------------------------------
                       Publication Estimates                                      Percentages
  -------------------- ---------------------------------------------------------- -------------
                       The error is the larger of:                                Value of Y
                                                                                  for Percent
                                                                                  Formula

  **Errors on Housing                                                             
  Units**                                                                         

  **Housing Unit       Z\~x\~ SQRT                                                1.000
  Characteristics Not  {264.79\~x\~A\~-\~.000296\~x\~A\^{2}}\~\\or\~Z\~x\~265     
  Listed in Tables 7A                                                             
  or 7B**                                                                         

  **Housing Unit       Z\~x\~ SQRT                                                1.324
  Characteristics^1^   {463.92\~x\~A\~-\~.000518\~A\^{2}}\~\\or\~Z\~x\~464        
  Listed in Table 7A**                                                            

  **Housing Unit       Z\~x\~ SQRT                                                1.539
  Characteristics^2^   {626.87\~x\~A-\~.000701\~x\~A\^{2}}\~\\or\~Z\~x\~627       
  Listed in Table 7B**                                                            

  **Errors on                                                                     
  Persons**                                                                       

  **Characteristics of Z\~x\~ SQRT                                                1.014
  Persons Not Listed   {273.98\~x\~A\~-\~.000124\~x\~A\^{2}}\~\\or\~Z\~x\~274     
  Below**                                                                         

                       **NOTE: For any of the person characteristics listed below 
                       that are cross-tabbed by Borough and Sub-borough use the   
                       formula for the specific characteristic listed below.      
                       Don\'t use the formulas listed below for cross-tabs of     
                       characteristics of persons listed below {e.g., Age by sex  
                       (males under 25), Age by Race (African Americans under     
                       25), or sex by race (white females)}. Use the formula      
                       above (Characteristics of Persons Not Listed Below).**     

  **Whites and other   Z\~x\~ SQRT                                                1.575
  Races and            {661.53\~x\~A\~-\~.000372\~x\~A\^{2}}\~\\or\~Z\~x\~662     
  Ethnicity**                                                                     

  **Males**            Z\~x\~ SQRT                                                1.575
                       {661.53\~x\~A\~-\~.000619\~x\~A\^{2}}\~\\or\~Z\~x\~662     

  **Females**          Z\~x\~ SQRT                                                1.575
                       {661.53\~x\~A\~-\~.000582\~x\~A\^{2}}\~\\or\~Z\~x\~662     

  **Persons under 25   Z\~x\~ SQRT                                                1.398
  yrs. old**           {521.06\~x\~A\~-\~.000236\~x\~A\^{2}}\~\\or\~Z\~x\~521     

  **African            Z\~x\~ SQRT                                                2.296
  Americans**          {1405.55\~x\~A\~-\~.003302\~x\~A\^{2}}\~\\or\~Z\~x\~1406   

  **Sub-borough and    Z\~x\~ SQRT                                                2.296
  Borough** ^3^        {1405.55\~x\~A\~-\~.000637\~x\~A\^{2}}\~\\or\~Z\~x\~1406   
  ---------------------------------------------------------------------------------------------

^1^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7A. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^2^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7B. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^3^ Exclude total population in households. Use the formula for
"Characteristics of Persons Not Listed Below" for these person
characteristics.

**Table 6: Errors for Staten Island**

  -----------------------------------------------------------------------------------------------
                       Publication Estimates                                        Percentages
  -------------------- ------------------------------------------------------------ -------------
                       The error is the larger of:                                  Value of Y
                                                                                    for Percent
                                                                                    Formula

  **Errors on Housing                                                               
  Units**                                                                           

  **Housing Unit       Z\~x\~ SQRT                                                  1.000
  Characteristics Not  {264.79\~x\~A\~-\~.001402\~x\~A\^{2}}\~\\or\~Z\~x\~265       
  Listed in Tables 7A                                                               
  or 7B**                                                                           

  **Housing Unit       Z\~x\~ SQRT                                                  1.324
  Characteristics^1^   {463.92\~x\~A\~-\~.002456\~A\^{2}}\~\\or\~Z\~x\~464          
  Listed in Table 7A**                                                              

  **Housing Unit       Z\~x\~ SQRT                                                  1.539
  Characteristics^2^   {626.87\~x\~A-\~.003318\~x\~A\^{2}}\~\\or\~Z\~x\~627         
  Listed in Table 7B**                                                              

  **Errors on                                                                       
  Persons**                                                                         

  **Characteristics of Z\~x\~ SQRT                                                  1.014
  Persons Not Listed   {273.98\~x\~A\~-\~.000601\~x\~A\^{2}}\~\\or\~Z\~x\~274       
  Below**                                                                           

                       **NOTE: For any of the person characteristics listed below   
                       that are cross-tabbed by Borough and Sub-borough use the     
                       formula for the specific characteristic listed below. Don\'t 
                       use the formulas listed below for cross-tabs of              
                       characteristics of persons listed below {e.g., Age by sex    
                       (males under 25), Age by Race (African Americans under 25),  
                       or sex by race (white females)}. Use the formula above       
                       (Characteristics of Persons Not Listed Below).**             

  **Whites and other   Z\~x\~ SQRT                                                  1.575
  Races and            {661.53\~x\~A\~-\~.001582\~x\~A\^{2}}\~\\or\~Z\~x\~662       
  Ethnicity**                                                                       

  **Males**            Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.002988\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Females**          Z\~x\~ SQRT                                                  1.575
                       {661.53\~x\~A\~-\~.002818\~x\~A\^{2}}\~\\or\~Z\~x\~662       

  **Persons under 25   Z\~x\~ SQRT                                                  1.398
  yrs. old**           {521.06\~x\~A\~-\~.001142\~x\~A\^{2}}\~\\or\~Z\~x\~521       

  **African            Z\~x\~ SQRT                                                  2.296
  Americans**          {1,405.55\~x\~A\~-\~.036998\~x\~A\^{2}}\~\\or\~Z\~x\~1,406   

  **Sub-borough and    Z\~x\~ SQRT                                                  2.296
  Borough** ^3^        {1,405.55\~x\~A\~-\~.003082\~x\~A\^{2}}\~\\or\~Z\~x\~1,406   
  -----------------------------------------------------------------------------------------------

^1^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7A. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^2^Use this formula only for estimates of the housing unit
characteristics [and]{.underline} subgroups listed in Table 7B. For
estimates of the housing unit

characteristics for subgroups not listed, use the first formula listed
above.

^3^ Exclude total population in households. Use the formula for
"Characteristics of Persons Not Listed Below" for these person
characteristics.

**Table 7A: Housing Unit Characteristics Associated with the Second of
Three Error Formulas**

For characteristics and subgroups matching to Table 7A, use the second
of the three housing unit error formulas.

+----------------------------------------+-----------------------------+
| **Characteristics**                    | **Applicable Subgroups**    |
+========================================+=============================+
| ● Race and Ethnicity of Householder    | Total Housing Units         |
|                                        |                             |
| (White, non-Hispanic and Black,        |                             |
| non-Hispanic)                          |                             |
+----------------------------------------+-----------------------------+
| ● Borough Totals                       | Renter Occupied             |
|                                        | (Stabilized, Mitchell Lama, |
|                                        | Public Housing) and         |
|                                        |                             |
|                                        | Owner Occupied              |
|                                        | (Condominiums and Total     |
|                                        | Cooperatives)               |
+----------------------------------------+-----------------------------+
| ● Sub-borough of Staten Island Totals  | Total Housing Units, Total  |
|                                        | Occupied Housing Units,     |
|                                        | Total Rental Housing Units  |
|                                        | and Total Occupied Rental   |
|                                        | Housing Units               |
+----------------------------------------+-----------------------------+
| ● Contract Rent \< \$300               | Total Housing Units and     |
|                                        | Total Occupied Housing      |
|                                        | Units                       |
+----------------------------------------+-----------------------------+
| ● Wheel Chair Accessibility            | All subgroups except        |
|                                        |                             |
|                                        | Renter Occupied -           |
|                                        | Controlled and              |
|                                        |                             |
|                                        | Owner Occupied -            |
|                                        | Conventional                |
+----------------------------------------+-----------------------------+
| ● Floor Unit is on (except basement)   |                             |
+----------------------------------------+-----------------------------+
| ● Access from Sidewalk to              |                             |
| Elevator/Unit without using Stairs     |                             |
+----------------------------------------+-----------------------------+
| ● Households Not Receiving Part of     |                             |
| Monthly Rent from Government Programs  |                             |
+----------------------------------------+-----------------------------+
| ● Condition of Building External       | Total Occupied and Total    |
| Walls, Windows, Stairways, and Floors  | Renter Occupied             |
| of Building                            |                             |
+----------------------------------------+-----------------------------+
| ● Number of Building Condition         |                             |
| Problems 1-4                           |                             |
+----------------------------------------+-----------------------------+

**Table 7B: Housing Unit Characteristics Associated with the Third of
Three Error Formulas**

For characteristics and subgroups matching to Table 7B, use the third of
the three housing unit error formulas.

+----------------------------------------+-----------------------------+
| **Characteristics**                    | **Applicable Subgroups**    |
+========================================+=============================+
| ● Sub-borough Totals (All Boroughs     | Total Housing Units, Total  |
| Except Staten Island)                  | Occupied Housing Units,     |
|                                        | Total Rental Housing Units  |
|                                        | and Total Occupied Rental   |
|                                        | Housing Units               |
+----------------------------------------+-----------------------------+
| ● Structure Classification - Multiple  | Total Housing Units and     |
| dwelling units                         |                             |
|                                        | Total Occupied Housing      |
|                                        | Units                       |
+----------------------------------------+-----------------------------+
| ● Structure Classification - One or 2  | Total Housing Units         |
| family house                           |                             |
+----------------------------------------+-----------------------------+
| ● Rent Control Status                  | Total Rental Housing Units  |
|                                        | and Total Occupied Rental   |
|                                        | Housing Units               |
+----------------------------------------+-----------------------------+
| ● Year Building Built                  | Total Occupied and Total    |
|                                        | Renter Occupied             |
+----------------------------------------+-----------------------------+
| ● Number of Stories in Building        |                             |
+----------------------------------------+-----------------------------+
| ● Number of Units in Building          |                             |
+----------------------------------------+-----------------------------+
| ● Presence of Owner in Building        |                             |
+----------------------------------------+-----------------------------+
| ● Elevator in Building with 2 or more  |                             |
| stories                                |                             |
+----------------------------------------+-----------------------------+
| ● State/City Assisted Cooperatives     | Total Owner Housing Units   |
|                                        | and Total Occupied Owner    |
|                                        | Housing Units               |
+----------------------------------------+-----------------------------+
| ● Private Cooperatives                 |                             |
+----------------------------------------+-----------------------------+
| ● Private Condominiums                 |                             |
+----------------------------------------+-----------------------------+