Frequencies for first 10,000 rows of pldel variable in natl1981 dataset :

   Place of |
   Delivery |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      9,904       99.04       99.04
          2 |         96        0.96      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016