README File for ACS 2005 Data Products Delivered via FTP

**NOTE. The data products are limited to the housing unit population and
exclude the population living in institutions, college dormitories, and
other group quarters.**

**I) Data Available at this FTP Site**

Six types of data products are provided on this site -- base tables,
profiles (demographic characteristics, social characteristics and
housing characteristics) subject tables, ranking tables, geographic
comparison tables and Selected Population Profiles. All data products
contained in this FTP site will be released by November 14 on American
FactFinder. Information about these products is available at the website
for the Guide to the ACS Data Products,
<http://www.census.gov/acs/www/Products/users_guide/index.htm>

Base tables provide basic housing and population characteristics. These
tables are the foundation upon which higher-level profiles are built.
The base tables come complete with the margin of error as well as the
lower bound and upper bound of a confidence interval. Both the margin of
error and the confidence interval were based on the 90% level of
confidence.

Profiles provide estimates of selected demographic, and selected social
characteristics for each geographic area. Each profile estimate is
accompanied by its margin of error and the confidence interval were
based on the 90% level of confidence.

Ranking tables show how States compare to each other for 70+ selected
characteristics.

Geographic Comparison Tables are single-variable tables comparing key
indicators for geographies other than states.

Subject Tables highlight a particular subject of interest. Each subject
table is accompanied by its margin of error and the confidence intervals
were based on the 90% level of confidence.

The "Selected Population Profile" is a single table that can be viewed,
or "iterated" for many race, ethnic and ancestry groups. The population
group choices are similar to those found in the Census 2000 Summary
Files 2 and 4, where you can find a hyperlink to a complete listing of
the Race, Ethnic and Ancestry Groups.

**II) Documentation Available at this FTP Site**

1\) The [Accuracy of the Data]{.underline} document for 2005 is
available on this site. This document provides data users with a basic
understanding of the sample design, estimation methodology, and accuracy
of the data. The filename for this document is:
Accuracy_of_the_Data_2005.doc.

2\) [Instructions for Applying Statistical Testing to ACS
Data]{.underline} are available in the following document:
ACS_2005_Statistical_Testing.doc

3\) A list of base tables that contain [geographic
restrictions]{.underline} can be found in the following spreadsheet:
GEORES.xls

4\) There is also a [Footnotes document for the data
products]{.underline} named Footnotes.xls located in the ftp upper
directory. This document contains the footnotes that a data user will
see when viewing any of these data products in American FactFinder when
the data are made public on November 14.

5\) [ACS 2005 Base Table Shells for Data Release]{.underline} are
located on the Guide to the ACS Data Products Webpage located on the
following URL:
<http://www.census.gov/acs/www/Products/users_guide/index.htm>

**III) Finding the Data**

Under the FTP directory, there are four sub-directories,
*Tables_Profiles_Subject_Tables, Ranking_Tables,
Geographic_Comparison_Tables, SPP (Selected Population Profiles)* and
four files: *Wave1Tables.zip, Wave2Tables.zip, Wave3Tables.zip* and
*Profiles.zip.*

**A. *Tables_Profiles_Subject_Tables***

The *Tables_Profiles_Subject_Tables* directory contains a spreadsheet
for the United States and a spreadsheet for each region and division.
Also, included are separate directories for each state (including the
District of Columbia) and geographic summary level. The state
directories contain one state spreadsheet and, depending upon the data
available, up to 17 subdirectories for the following geographic levels:

Geography summary level Description

050 State-County

060 State-County-County Subdivision

160 State-Place

250 American Indian Area/Alaska Native Area/Hawaiian Home Land

310 Metropolitan Statistical Area/Micropolitan Statistical Area

312 Metropolitan Statistical Area/Micropolitan Statistical
Area-State-Principal City

314 Metropolitan Statistical Area/Micropolitan Statistical
Area-Metropolitan Division

330 Combined Statistical Area

335 Combined New England City and Town Area

350 New England City and Town Area

352 New England City and Town Area-State-Principal City

355 New England City and Town Area (NECTA)-NECTA Division

400 Urban Area

500 State-Congressional District (109th)

795 State-Public Use Microdata Area (5%)

950 State-School District (Elementary)

960 State-School District (Secondary)

970 State-School District (Unified)

Within each spreadsheet are the following 6 worksheets:

ACS Data Products -- Contains a list of data products available for a
specific geography

Base Tables -- Contains all of the most detailed tables for that
geography

Profile-Demographic Characteristics -- Contains the profile estimates
for selected demographic profile

Profile-Social Characteristics -- Contains the profile estimates for
selected social characteristics profile

Profile-Economic Characteristics -- Contains the profile estimates for
selected economic characteristics

Profile- Housing Characteristics -- Contains the profile estimates for
selected housing characteristics

Subject Tables -- Contains approximately 50 tables that highlight
particular subjects of interest.

**Margin of error (MOE)**

A margin of error is the maximum difference between an estimate and its
upper or lower confidence bounds. A confidence interval can be created
by adding the margin of error to the estimate (for an upper bound) and
subtracting the margin of error from the estimate (for a lower bound).
In doing this, it is important not to allow either the lower bound or
the upper bound of the confidence interval to go beyond the range of
possible values for an estimate. For example, an estimate of children
enrolled in school in a geographic area cannot be less than 0.
Therefore, its lower bound can also not be less than 0. All published
margins of error for the American Community Survey are based on a 90
percent confidence level.

The Base Tables worksheets contains the following file layout:

Column 1 -- Table ID

Column 2 -- Line Number within Table

Column 3 -- Line Description

Column 4 -- Direct Estimate

Column 5 -- Margin of Error

Column 6 -- Lower Bound Estimate

Column 7 -- Upper Bound Estimate

The Profile Characteristics worksheets contains the following file
layout:

Column 1 -- Line Description

Column 2 -- Direct Estimate

Column 3 -- Margin of Error

Column 4 -- Lower Bound Estimate

Column 5 -- Upper Bound Estimate

Place of Work Data Products are available under the *Place_of_Work*
directory in the same fashion as the data is organized for the resident
data products above.

# B. Ranking_Tables

Under the *Ranking_Tables* directory there is a spreadsheet for each
ranked characteristic at the state level.

The Ranking Tables file contains the following file layout:

Column 1 -- Rank

Column 2 -- State

Column 3 -- Median

Column 4 -- Margin of Error

# C. Geographic_Comparison_Tables

Under the *Geographic_Comparison_Tables* directory there is a
spreadsheet for each characteristic at the state by county and state by
place level.

The Geographic Comparison Tables file contains the following file
layout:

Column 1 -- Geographic Area

Column 2 -- Estimate

Column 3 -- Margin of Error

D.  ***SPP (Selected Population Profiles)***

The "Selected Population Profile" is a single table that can be viewed,
or "iterated" for many race, ethnic and ancestry groups. The population
group choices are similar to those found in the Census 2000 Summary
Files 2 and 4. Selected Population Profile\'s are published for the
nation, states, and other geographic areas that have a total population
of 1,000,000 and a group or iterated population of 65,000 or greater.

Under the SPP directory there will be two Excel spreadsheets Race.xls
and Ancestry.xls these two spreadsheets provide information on what
Selected Population Profiles are published for what geography and what
iteration. The Ancestry.xls and Race.xls (Race-Hispanic Origin codes)
group spreadsheets will contain the following two worksheets:

> GeobyRace - Geography as rows and Race\\Hispanic Origin (or Ancestry)
> as columns
>
> RacebyGeo - Race\\Hispanic Origin (or Ancestry) as rows and Geography
> as columns

If an iterated Selected Population Profiles is published for the
specific geography and iteration an \"X\" is placed in that cell.

Under the *SPP* directory there will be two sub directories
*Race_Ancestry_Hispanic_Origin* and *Geography* each of these sub
directories will contain individual Selected Population Profiles. The
*Race_Ancestry_Hispanic_Origin* directory will contain sub directories
by each Iteration (example: "Spaniard") and with in this directory a
spreadsheet that contains the Selected Population Profiles estimates for
example if you where looking for "Spaniards" in the state of Iowa they
could be found at
www2.census.gov/acs2005/SPP/Race_Ancestry_Hispanic_Origin/
Spaniard/State/California.xls and you will be able to view all the other
geographies that were published for "Spaniards" in the Spaniard
directory. The SPP data can also be found in reverse using the
*Geography* directory, which will have, sub directories of geographic
summary level by individual geographies in that summary level for
example www2.census.gov/acs2005/SPP/Geography/State/California/ would
contain all of the published SPP's for the state of California.

The spreadsheets themselves contain 5 columns of data

Column 1 -- Line Description

Column 2 -- Total Population Estimate

Column 3 -- Total Population Margin of Error

Column 4 -- Iterated Population Estimate

Column 5 -- Iterated Population Margin of Error

**E. *Wave1Tables.zip, Wave2Tables.zip, Wave3Tables.zip***

The Wave1Tables.zip, Wave2Tables.zip, Wave3Tables.zip files contain
three types of data. First a file that contains information regarding
the geographies the ACS published in 2005 named Geography.txt. Secondly
a file named WaveXTables.txt (where X is the wave), this file contains
information regarding each Base Table the ACS published in 2005 in that
wave. Lastly within the Wave1Tables.zip,Wave2Tables.zip and
Wave3Tables.zip there are individually compressed ASCII files and SAS
datasets of each Wave 1,Wave 2 and Wave 3 Base Table the ACS released in
2005.

2005 ACS Geography information (Geography.txt)

Column 1 -- GeographyID

Column 2 -- Name

Geography.txt is a tab delimited text file; the first column named
GeographyID is the ACS Geography code for each published 2005 ACS area.
The second column Name is the corresponding name to each GeographyID.

2005 ACS Wave 1,2 and 3 Base Table information (WaveXTables.txt)

Column 1 -- TableID

Column 2 -- Cells

Column 3 -- Table_Title

WaveX.txt is a tab delimited text file; the first column named TableID
is the corresponding ACS Base Table identifier, it is also can be linked
to the name of the compressed ASCII files. The second column Cells is
the number of individual estimates in the Base Table. The third column
named Table_Title is the actual alphabetic name of the table (these are
the same names as what appears in the spreadsheets).

Compressed ASCII files of Wave 1 Base Tables, Wave 2 Base Tables, and
Wave 3 Base Tables (B\*\*\*\*\*\*.zip or C\*\*\*\*\*\*.zip)

NOTE: Each .zip file contains an ASCII file with the same naming
convention of the TableID with a ".DAT" file extension, these files will
need to be uncompressed.

Column 1 -- TableID

Column 2 -- GeographyID

Column 3 + -- Estimate / Margin of Error

The compressed ASCII files have a space delimiter and have the following
layout; the first column of TableID is the corresponding ACS Base Table
identifier and can be linked to the TableID in the WaveXTables.txt file.
The second column named GeographyID is the ACS Geography code for each
published 2005 ACS area for that specific Base Table and can be linked
to the GeographyID in the Geography.txt file. The third column contains
all the Estimates and Margin of Error with in the table repeating for
each value.

Below is example of reading in all three of these files using B01002.DAT
as the example ASCII Wave 1, 2 and 3 Base Table file.

[Example Record B01002.DAT]{.underline}

B01002 16000US1271000 36.2 +/-1.0 35.9 +/-1.2 36.5 +/-1.3

The TableID in this file provides the link to Wave1Tables.txt

[Entry in Wave1Tables.txt]{.underline}

B01002 3 MEDIAN AGE BY SEX

The GeographyID in B01002.DAT provides the link to Geography.txt

[Entry in Geography.txt]{.underline}

16000US1271000 Tampa city, Florida

In the example above we can see the record from B01002.DAT is a 3 cell
Median Age By Sex Wave 1 Base Table for Tampa city, Florida.

Compressed SAS datasets of Wave 1 Base Tables, Wave 2 Base Tables, Wave
3 Base Tables (B\*\*\*\*\*\*.zip or C\*\*\*\*\*\*.zip)

NOTE: Each .zip file contains a SAS dataset with the same naming
convention of the TableID with a ".SAS7BDAT" file extension.

Variable 1 -- TableID

Variable 2 -- GeographyID

Variable 3 -- Estimate

Variable 4 +- Margin of Error

Variables 3 and 4, containing the Estimate / Margin of Error repeat,
based on the number of cells in the table.

**NOTE: Information regarding ASCII Wave 1 and 2 Base Table files**

**Some data values represent unique situations where either:**

**a) the information to be conveyed is an explanation for the absence of
data, represented by a symbol in the data display, such as \"(X)\", or**

**b) the information to be conveyed is an open-ended distribution, such
as 115 or greater, represented by 115+.**

**Following are the special data values (and their meaning) for case
(a), which can appear in any 2005 ACS table or map product:**

**-999999999 = N Indicates that an estimate or its margin of error
cannot be provided because the number of sample cases is too small for
the given geographic area.**

**-888888888 = (X) Indicates that the estimate is not applicable or not
available.**

**-777777777 = (Z) Estimate is not available for an undefined reason.**

**-666666666 = - Indicates that no sample observations were available to
compute an estimate, or a ratio of medians cannot be calculated because
one or both of the median estimates falls in the lowest interval or
upper interval of an open-ended** **distribution.**

**F. *Profiles.zip***

prof.txt information

Column 1 -- ProfileID

Column 2 -- GeographyID

Column 3 + -- Estimate / Margin of Error

The prof.txt ASCII files have a space delimiter and have the following
layout; the first column of ProfileID. The second column named
GeographyID is the ACS Geography code for each published 2005 ACS area
for that specific Profile and can be linked to the GeographyID in the
Geography.txt file. The third column contains all the Estimates and
Margin of Error with in the table repeating for each value.

2005 ACS Geography information (Geography.txt)

Column 1 -- GeographyID

Column 2 -- Name

Geography.txt is a tab delimited text file; the first column named
GeographyID is the ACS Geography code for each published 2005 ACS area.
The second column Name is the corresponding name to each GeographyID.

2005 ACS Wave 1,2 and 3 Profiles (Wave1,2and3Profiles.txt)

Column 1 -- TableID

Column 2 -- Cells

Column 3 -- Table_Title

Wave1,2and3Profiles.txt is a tab delimited text file; the first column
named TableID is the corresponding ACS Profile identifier, it is also
can be linked to the name of the compressed ASCII files. The second
column Cells is the number of individual estimates in the Profile. The
third column named Table_Title is the actual alphabetic name of the
table (these are the same names as what appears in the spreadsheets).

2005 ACS Wave 1,2 and 3 Profile Stubs (prof_stubs.xls)

Column 1 -- TableID

Column 2 -- Line

Column 3 -- Stub

Column 4 -- Estimate

Column 5 -- Margin of Error

The prof_stubs.xls file contains all of the stubs for each of the data
lines within wave 1,2 and 3 profiles. The first column of TableID
corresponds to the Profile Table Identification number (DP01, DP02,
etc). The second column line is the line number in each one of the
profiles that the stub information pertains too. The third column Stub
is the corresponding metadata for each data line in the wave 1,2 and 3
profiles. Columns 4 and 5 are the repeating estimate and margin of error
columns, the estimates and margin of errors can be a number (#), a
dollar value (\$) or a percent (%).

**NOTE: Information regarding ASCII Wave 1,2 and 3 Profile files**

**Some data values represent unique situations where either:**

**a) the information to be conveyed is an explanation for the absence of
data, represented by a symbol in the data display, such as \"(X)\", or**

**b) the information to be conveyed is an open-ended distribution, such
as 115 or greater, represented by 115+.**

**Following are the special data values (and their meaning) for case
(a), which can appear in any 2005 ACS table or map product:**

**-999999999 = N Indicates that an estimate or its margin of error
cannot be provided because the number of sample cases is too small for
the given geographic area.**

**-888888888 = (X) Indicates that the estimate is not applicable or not
available.**

**-777777777 = (Z) Estimate is not available for an undefined reason.**

**-666666666 = - Indicates that no sample observations were available to
compute an estimate, or a ratio of medians cannot be calculated because
one or both of the median estimates falls in the lowest interval or
upper interval of an open-ended** **distribution.**

**IV) Base Tables and Profile Lines that are suppressed**

In certain geographic areas, there may not be sufficient sample cases to
support an estimate or group of estimates. In that case, an "N" will be
displayed in place of the estimate and its margin of error. For base
tables, all the estimates in the table will be suppressed. For the
profile tables, only the affected profile lines will be suppressed.

**Other Sources of the Data**

**V) FTP File Transfer**

To facilitate transferring files, we suggest using features commonly
found in most vendors' FTP utility. When testing the download in a PC
environment, we used the ws_ftp product. This product, and many other
FTP products developed for the PC environment, allows individual or
multiple file selection using the control key or block multiple file
selection using the shift key.