Frequencies for first 10,000 rows of proc5per variable in nhamcsopd1994 dataset :

 service #5 |
  performed |
 or ordered |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,977       99.77       99.77
          1 |         14        0.14       99.91
          2 |          3        0.03       99.94
          3 |          6        0.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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