Frequencies for first 10,000 rows of vyear variable in nhamcsed1993 dataset :

    year of |
  visit - 2 |
     digits |      Freq.     Percent        Cum.
------------+-----------------------------------
         92 |        114        1.14        1.14
         93 |      9,886       98.86      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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