Frequencies for first 10,000 rows of lab variable in namcs2007 dataset :

is lab testing |
  performed at |
       office? |      Freq.     Percent        Cum.
---------------+-----------------------------------
           yes |      6,711       67.11       67.11
            no |      3,289       32.89      100.00
---------------+-----------------------------------
         Total |     10,000      100.00

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