Frequencies for first 10,000 rows of ectoe variable in namcs2008 dataset :

  practice has |
      computer |
    system for |
    orders for |
        tests? |      Freq.     Percent        Cum.
---------------+-----------------------------------
         blank |         57        0.57        0.57
       unknown |         34        0.34        0.91
           yes |      4,162       41.62       42.53
            no |      5,615       56.15       98.68
    turned off |        132        1.32      100.00
---------------+-----------------------------------
         Total |     10,000      100.00

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