BOX 3-1 Mail Response and Return Rates
Definitions and Uses
The mail response rate is defined as the number of households returning a questionnaire by mail divided by the total number of questionnaires sent out in mailback areas. Achieving a high mail response rate is important for the cost and efficiency of the census because every returned questionnaire is one less household for an enumerator to follow up in the field.
The mail return rate is defined as the number of households returning a questionnaire by mail divided by the number of occupied households that were sent questionnaires in the mailback areas. This rate is an indicator of public cooperation. Achieving a high mail return rate (at least to the level of 1990) is important because of evidence from 1990 that mail returns are more complete than enumerator-obtained returns.
In 2000, because of the alternative modes by which households could fill out their forms, the numerator of both “mail” responses and “mail” returns included responses submitted on the Internet, over the telephone, and on “Be Counted” forms. The denominator of the mail response rate included all addresses on the April 1, 2000, version of the MAF, covering both mailout/mail back and update/leave areas. The denominator of the mail return rate excluded addresses on the MAF that field follow-up determined were vacant, nonresidential, or nonexistent.
Rates, 1970–2000 Censuses
Differences in Mail Return Rates: Short and Long Forms
Return rates of long forms are typically below the return rates of short forms. This difference widened substantially in 2000.