Frequencies for first 10,000 rows of retprn variable in nhamcsopd1999 dataset :

  return to |
    clinic, |
 p.r.n. (as |
    needed) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,892       78.92       78.92
          1 |      2,108       21.08      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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