Frequencies for first 10,000 rows of mildif13 variable in h84 dataset :

 DIFFICULTY |
  WALKING A |
       MILE |      Freq.     Percent        Cum.
------------+-----------------------------------
         -8 |         12        0.12        0.12
         -1 |      8,973       89.73       89.85
          1 |        137        1.37       91.22
          2 |        209        2.09       93.31
          3 |        214        2.14       95.45
          4 |        455        4.55      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Feb 2018