Frequencies for first 10,000 rows of proc5per variable in namcs1994 dataset :

 service #5 |
  performed |
 or ordered |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,981       99.81       99.81
          1 |          4        0.04       99.85
          2 |         13        0.13       99.98
          3 |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016