Skip to content U.S. Department of Transportation/Federal Highway AdministrationU.S. Department of Transportation/Federal Highway Administration

Office of Planning, Environment, & Realty (HEP)
Planning · Environment · Real Estate

HEP Events Guidance Publications Glossary Awards Contacts

CTPP 2000 Frequently Asked Questions

PDF files can be viewed with the Acrobat® Reader®

  1. CTPP 2000 Access Software Troubleshooting
  2. Census, ACS, and CTPP: Some General Information and Trouble Shooting (March 13, 2007):
  3. What data are available from the CTPP?
  4. How do I access CTPP data?
  5. What are some uses of CTPP data?
  6. How did the CTPP come about?
  7. There are 3 Parts to CTPP data, what are they and how do they differ?
  8. How do the 1990 and 2000 CTPP data sets differ?
  9. What are the tables available in CTPP 2000?
  10. What should I do when I get my CTPP CD with the CTPP Access Tool a.k.a the Browser?
  11. Why do my employment numbers in CTPP look lower than total employment in my area?
  12. Why do my Part 3 tables look so odd?

2. Census, ACS, and CTPP: Some General Information (March 13, 2007):

Census 2010

Census 2010 will be only a SHORT FORM Census. This means NO LONG FORM questions. The LONG FORM questions are asked in a continuous survey called the American Community Survey (www.census.gov/acs/www).

For a list of questions in Census 2010, please see an article in the Wall Street Journal Feb 23, 2007. There are 6 basic questions and an additional 3 for "householder" which have not yet been determined.

American Community Survey

Please see http://www.fhwa.dot.gov/planning/census_issues/american_community_survey/ This link includes links to training on ACS and a new book by Cynthia Taueber.

Census Transportation Planning Package

Main website: http://www.fhwa.dot.gov/planning/census_issues/ctpp/

Training: http://www.fhwa.dot.gov/planning/census_issues//ctpp/training/

Top of Page

3. What data are available from the CTPP?

For both 1990 and 2000, the following data sets are available:

In addition, the data sets may be broken down into following geographies (varies for each data set and time period):

  • TAZs
  • Primary Metropolitan Statistical Area (PMSA)
  • Place
  • County
  • Metropolitan Statistical Area (MSA)
  • State
Top of Page

4. How do I access CTPP data?

Please refer to the Data Products page for accessing CTPP data.

Top of Page

5. What are some uses of CTPP data?

Please refer to the following status reports for some applications of CTPP data:

Top of Page

6. How did the CTPP come about?

Please click here for more information on the history of the CTPP.

Top of Page

7. There are three Parts included in CTPP data: what are they and how do they differ?

The CTPP 2000 is divided into three parts:

The CTPP 1990 is divided into three parts:

Statewide

Urban

To learn more and access CTPP data products, visit the Data Products page.

Top of Page

8. How do the 1990 and 2000 CTPP data sets differ?

Top of Page

9. What are the tables available in CTPP 2000?

Top of Page

10. What should I do when I get my CTPP CD with the CTPP Access Tool a.k.a the Browser?

Also read the following for PART 3.

Top of Page

11. Why do my employment numbers in CTPP look lower than total employment in my area?

Please see http://www.fhwa.dot.gov/planning/census_issues/ctpp/training/ctppatwork.cfm and http://www.fhwa.dot.gov/planning/census_issues/ctpp/status_report/sr0503.cfm "A discussion on some Census terms"

Generally speaking, about 25 percent of workers do not provide sufficient information about workplace locations, so their workplace is imputed using travel time, travel mode, industry and occupation.

Please refer to the following articles from the January, 2004 and the May, 2003 CTPP Status Reports for more in-depth information on accessing and understanding CTPP data: "CTPP Workers at Work Compared to Other Employment Estimates" and "A discussion on some Census terms" respectively. Also, click here for an article on "CTPP Workers-at-Work Compared to Other Employment Estimates" .

Top of Page

12. Why do my Part 3 tables look so odd?

SOME of the Part 3 tables were subject to THRESHOLDS. All of the CTPP is subject to ROUNDING. Part 3 Tables 1 and 2 are NOT subject to thresholds.

Please see http://www.fhwa.dot.gov/planning/census_issues/ctpp/training/balance.cfm and also see Using Tables from Part 3 of CTPP: A note of caution

However, those subject to the thresholds have a LOT of SUPPRESSION for small geography. http://www.trbcensus.com/notes/small_area_data.pdf

One way to get around rounding and thresholds for Part 3 is to use Table 3-14 and Table 3-8. For instructions, please see http://www.chrispy.net/pipermail/ctpp-news/2005-May/001338.html

Top of Page
Updated: 11/20/2013
HEP Home Planning Environment Real Estate
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000