Frequencies for first 10,000 rows of totamb variable in namcs1998 dataset :

     total # of ambulatory surgical |
                         procedures |      Freq.     Percent        Cum.
------------------------------------+-----------------------------------
                                  0 |      9,726       97.26       97.26
                                  1 |        256        2.56       99.82
                                  2 |         18        0.18      100.00
------------------------------------+-----------------------------------
                              Total |     10,000      100.00

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