Structure of 2001 NHTS Pre-9/11 and Post-9/11 Data Files,,,,,
Data Files,Information Included,Record Level,ID Variables,Weight,Replicates
Pre-9/11 Person,"These files include education level, worker status, occupation and employer information, driver status, annual miles driven, country of birth, income, and other characteristics of the person.",One record per person (person whose assigned travel date is before or on 9/25/2001),HOUSEID and PERSONID,WTPRPRE,PERPRE1-PERPRE99
Post-9/11 Person,,One record per person (person whose assigned travel date is after 9/25/2001),HOUSEID and PERSONID,WTPRPST,PERPST1-PERPST99
Pre-9/11 Long-Distance Trip,"Information on these files includes trip purpose, trip distance, and mode of transportation used to and from destination. Household and person characteristics are included with long-distance trip characteristics.",One record per long-distance trip (trip taken by person who is in the pre-9/11 Person-level data file),HOUSEID and PERSONID,WTLDPRE,LDPRE1-LDPRE99
Post-9/11 Long-Distance Trip,,One record per long-distance trip (trip taken by person who is in the post-9/11 person-level data file),HOUSEID and PERSONID,WTLDPST,LDPST1-LDPST99