Frequencies for first 10,000 rows of prov0750 variable in pos1999 dataset :

technologis |
 ts - bs/ba |
     degree |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,989       99.89       99.89
          1 |          7        0.07       99.96
          2 |          3        0.03       99.99
          9 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016