Frequencies for first 10,000 rows of uop_tocol variable in linkpe2009psden dataset :

  Tocolysis |
        U;R |
(f_uop_toco |
l rep flag) |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        156        1.56        1.56
          2 |      9,780       97.80       99.36
          9 |         64        0.64      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015