Frequencies for first 10,000 rows of agefl variable in nhamcsed2013 dataset :

Was patient age reported, calculated or |
                               imputed? |      Freq.     Percent        Cum.
----------------------------------------+-----------------------------------
Age calculated by NCHS based on reporte |      9,990       99.90       99.90
Age entered in survey instrument withou |         10        0.10      100.00
----------------------------------------+-----------------------------------
                                  Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 7 Nov 2016