Frequencies for first 10,000 rows of prov2240 variable in pos1991 dataset :

      spec: |
neurologica |
          l |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,683       96.83       96.83
          N |        261        2.61       99.44
          Y |         56        0.56      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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