Frequencies for first 10,000 rows of prov2210 variable in pos1992 dataset :

       srv: |
 laboratory |
 (clinical) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,851       88.51       88.51
          0 |         13        0.13       88.64
          1 |        857        8.57       97.21
          2 |        217        2.17       99.38
          3 |         62        0.62      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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