Frequencies for first 10,000 rows of mrace variable in natl1970 dataset :

    Race of |
     Mother |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      6,749       67.49       67.49
          2 |      3,202       32.02       99.51
          3 |          2        0.02       99.53
          4 |          2        0.02       99.55
          7 |         18        0.18       99.73
          8 |          9        0.09       99.82
          9 |         18        0.18      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016