Frequencies for first 10,000 rows of pastvis variable in namcs2005 dataset :

   if yes, how |
     many past |
visits in last |
    12 months? |      Freq.     Percent        Cum.
---------------+-----------------------------------
          None |        491        4.91        4.91
           1-2 |      2,907       29.07       33.98
           3-5 |      3,113       31.13       65.11
     6 or more |      2,525       25.25       90.36
Not applicable |        964        9.64      100.00
---------------+-----------------------------------
         Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016