Frequencies for first 10,000 rows of lab_srvc_cd variable in pos2007 dataset :

       srv: |
 laboratory |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      7,861       78.61       78.61
          0 |      1,460       14.60       93.21
          1 |         74        0.74       93.95
          2 |        548        5.48       99.43
          3 |         57        0.57      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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