2000 Census

Pursuant to a congressional request, GAO provided information on short- and long-form questionnaire response rates, focusing on the: (1) 2000 Census; (2) 1998 Census Dress Rehearsal; (3) 1990 Census; and (4) 1988 Census Dress Rehearsal.

GAO noted that: (1) during the 1990 and 2000 Census cycles, questionnaire response rates were higher for the short-form questionnaire than for the long-form questionnaire; (2) however, the gap between the two rates has generally widened over time; (3) for example, the differential between the short- and long-form response rates ranged from 5.1 percentage points to 8.7 percentage points during the 1988 Dress Rehearsal for the 1990 Census; (4) a decade later, during the Dress Rehearsal for the 2000 Census, the differential ranged from 8.2 percentage points to 14.7 percentage points; (5) for the 2000 Census, preliminary Bureau of the Census data show that the response rate differential for the 2000 Census is 12.5 percentage points--over twice that of the 1990 Census; (6) short- and long-form differential mail return rates have increased over time; (7) during the 1998 Dress Rehearsal, the Bureau mailed a second replacement questionnaire to all housing units located in mailout/mailback areas; (8) the Bureau hoped that the second questionnaire would help improve the response rate; and (9) although response rates in both Dress Rehearsal sites increased after the replacement mailing, the differential response rates between the short- and long-form questionnaires did not change significantly--decreasing by 2.5 percentage points and increasing by 0.1 percentage point.