Frequencies for first 10,000 rows of pldel variable in natl1987 dataset :

   Place of |
   Delivery |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      9,940       99.40       99.40
          2 |         60        0.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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