Frequencies for first 10,000 rows of prv_hypectrl variable in mcbsatc2013 datas

      Level |
 confidence |
control bld |
   pressure |      Freq.     Percent        Cum.
------------+-----------------------------------
         -8 |         71        0.71        0.71
         -7 |          4        0.04        0.75
          1 |      1,818       18.18       18.93
          2 |      2,041       20.41       39.34
          3 |      1,381       13.81       53.15
          4 |        707        7.07       60.22
          . |      3,978       39.78      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 24 May 2016