Frequencies for speclma variable in impact2007 dataset :

    Special |
  Exception |
      Labor |
Market Area |
         if |
 applicable |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      3,659       99.51       99.51
      10900 |          1        0.03       99.54
      16220 |          2        0.05       99.59
      16974 |          2        0.05       99.65
      22020 |          1        0.03       99.67
      25060 |          1        0.03       99.70
      33540 |          2        0.05       99.76
      35644 |          5        0.14       99.89
      37964 |          2        0.05       99.95
      43620 |          2        0.05      100.00
------------+-----------------------------------
      Total |      3,677      100.00

by Jean Roth , jroth@nber.org , 17 Mar 2016