Frequencies for a_c1_36 variable in snf_rollup2540_96_2011 dataset :

    a_c1_36 |      Freq.     Percent        Cum.
------------+-----------------------------------
      33079 |          1        0.06        0.06
      77371 |          1        0.06        0.11
     317587 |          1        0.06        0.17
          . |      1,806       99.83      100.00
------------+-----------------------------------
      Total |      1,809      100.00

by Jean Roth , jroth@nber.org , 17 Feb 2018