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

   Ever has |
    trouble |
concentrati |
         ng |      Freq.     Percent        Cum.
------------+-----------------------------------
         -8 |         30        0.30        0.30
         -7 |          3        0.03        0.33
          1 |      2,268       22.68       23.01
          2 |      7,699       76.99      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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