For directions on reading the variable description see Data Dictionary Introduction.

Availability: 
 

1850	1860	1870	1880	1900	1910	1920	1940	1950	1960	1970	1980	1990
X	X	X	X	X	X	X	X	X	X	X	X	X

Universe: 
All persons. 

Description: 
SLWT indicates the number of persons in the general population represented by each sample-line person in 1940 and 1950. It is especially useful in 1940 because the sample-line records in that year are not representative (unlike 1950 where sample line persons are a flat 1-in-330 sample of the population). To obtain representative sample-line statistics in 1940, users should apply SLWT or select an unweighted subset of sample lines using SEFLWTSL. In both 1940 and 1950, SLWT takes a value of zero for non-sample-line persons. For a further explanation of sample weights see the Chapter 1, "Introduction."

Comparability: 

SLWT works identically for 1940 and 1950. For years in which there is no sample-line record, SLWT is the same as person weight, PERWT (the number of persons in the population represented by the case). If no sample-line variables are used, SLWT is unnecessary. See Chapter 2, "Sample Designs."

Codes: 

See text above.