Frequencies for first 10,000 rows of chow_prior_dt variable in pos2001 dataset :

      prior |
  admission |
 suspension |
       date |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,999       99.99       99.99
   19860530 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017