Frequencies for first 10,000 rows of uca_spina variable in natlterr2009 dataset :

      Spina |
bifida/Meni |
ngocele RFP |
753=f_uca_s |
   pina U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          3        0.03        0.03
          2 |      8,633       86.33       86.36
          9 |      1,364       13.64      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015