Frequencies for first 10,000 rows of prov2210 variable in pos1998 dataset :

       srv: |
 laboratory |
 (clinical) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,805       88.05       88.05
          0 |          9        0.09       88.14
          1 |        880        8.80       96.94
          2 |        229        2.29       99.23
          3 |         77        0.77      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016