Frequencies for first 10,000 rows of lab_srvc_cd variable in pos2012 dataset :

   Service: |
 Laboratory |      Freq.     Percent        Cum.
------------+-----------------------------------
          . |      8,393       83.93       83.93
          0 |      1,074       10.74       94.67
          1 |         67        0.67       95.34
          2 |        433        4.33       99.67
          3 |         33        0.33      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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