Frequencies for first 10,000 rows of totdiag variable in nhamcsopd1999 dataset :

    total # of diagnostic/screening |
                           services |      Freq.     Percent        Cum.
------------------------------------+-----------------------------------
                                  0 |      2,339       23.39       23.39
                                  1 |      2,920       29.20       52.59
                                  2 |      2,195       21.95       74.54
                                  3 |      1,246       12.46       87.00
                                  4 |        593        5.93       92.93
                                  5 |        331        3.31       96.24
                                  6 |        172        1.72       97.96
                                  7 |        103        1.03       98.99
                                  8 |         62        0.62       99.61
                                  9 |         14        0.14       99.75
                                 10 |         10        0.10       99.85
                                 11 |          7        0.07       99.92
                                 12 |          5        0.05       99.97
                                 14 |          2        0.02       99.99
All boxes blank, including None box |          1        0.01      100.00
------------------------------------+-----------------------------------
                              Total |     10,000      100.00

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