da3241-da3247 are 1968-1974 Natality data files from ICPSR

3241 -> 1968
3242 -> 1969
3244 -> 1970
3243 -> 1971
3245 -> 1972
3246 -> 1973
3247 -> 1974

ICPSR data files are available from the Harvard-MIT Data Center.
The documentation is freely available at www.icpsr.umich.edu.

Prior to 1972, data are based on a 50-percent sample 
of birth certificates from all States. 
Beginning in 1972, data are based on a 100-percent sample 
of birth certificates from some states and on a 50-percent sample 
from the remaining States.

Jean Roth, jroth@nber.org, May 28, 2002