The Census Bureau is considering a proposal which might replace the traditional long form content sample in the 2000 census with a "Continuous Measurement" (CM) program which would collect the same information throughout the decade. The Continuous Measurement system would consist of:

i) an ongoing field operation to locate and update a sample of addresses from the Census Bureau's Master Address File (MAF), which is linked to the TIGER geographic database;
ii) a large Intercensal Long Form (ILF) survey;
iii) a Program of Integrated Estimates (PIE) to combine data from the ILF, other household surveys such as the Current Population Survey (CPS) and the Survey of Income and Program Participation (SIPP), the previous census short form, and demographic estimates derived from administrative sources, to make small-area estimates.

Although the idea of "spreading out the census" has been suggested at least since Eckler (1972), it began to be given more serious attention after the 1990 census as discussed in Melnick (1991), Subcommittee on Census and Population (1992), Sawyer (1993).

The proposal draws heavily on ideas of Kish (1981, 1990) and a previous Census Bureau proposal by Herriot, Bateman, and McCarthy (1989), as well as estimation ideas suggested by Herriot and Schneider (1990). The major development since these earlier proposals is the availability of the MAF, which is already being developed as a source of addresses for the 2000 Census.

This paper describes the prototype design being considered for the CM system, the reasons for selecting it, and plans for testing and evaluation of CM. Additional details of the design are given in Alexander (1993), which includes additional references.