The 2010 Census mail participation rate of 72% has matched the 2000 Census rate, and Census Bureau officials have released data indicating that sending replacement questionnaires to low-responding areas may have played a role. Census officials also credit aggressive outreach and advertising for boosting mail response.

According to the third page of this handout from yesterday’s news briefing, households in areas that received a single mailing returned their questionnaires at a slightly lower rate than in 2000. Areas that received replacement questionnaires, either in a targeted or blanket mailing, had mail participation rates slightly higher than in 2000. Replacement questionnaires were not sent out in the 2000 Census.

Census-takers begin knocking on doors this weekend to obtain information from households for which a questionnaire was not received.