Accessibility Data Files
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1995 - 2005
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This data was created during the Access to Destinations research project. Project reports and documentation are available at http://www.access.umn.edu/publications/related/destinations/

### Auto

- All auto accessibility data is in a single file for each year.
- Data is at the TAZ level using TAZ definitions from 2000. The taz_2000 field identifies the origin TAZ for each row.
- Data field names indicate the travel time threshold (in minutes), the destination type, and the departure time:

    - 5, 10, 15, etc : travel time threshold in minutes
    - pop, emp, lab : population, employment, labor
    - am, pm, op : AM peak period, PM peak period, Off-Peak
    - For example, the field 'l30emp95am' gives the number of jobs reachable within 30 minutes during the AM peak period.

### Transit

- Transit accessibility data is in separate files based on destination type. Currently, only job accessibility data is available.
- Data is at the block level using Census block definitions from 2000. The originid field identifies the GEOID for an individual block.
- Data fields identify the departure time and travel time thresholds:

    - hr : gives the departure hour, in 24-hour format. 8 indicates 8:00 AM; 17 indicates 5:00 PM.
    - cutoffXX : XX indicates the travel time threshold, in minutes.

2010
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- All accessibility data is in separate files based on destination type, mode, departure time, and (if necessary) geography type. For example, the file 'acc_jobs2010_autoAM2010_taz2000.csv' contains data on auto accessibility to jobs during the AM peak period in 2010 at the TAZ level (based on 2000 TAZ definitions).
- Data fields identify the origin and travel time threshold:

    - taz : identifies a TAZ based on 2000 TAZ definitions.
    - tXX : gives the number of opportunities that can be reached within XX minutes
    - The OBJECTID field can be ignored (if present).