Frequencies for first 10,000 rows of ume_vac variable in natl2012 dataset :

 Vacuum RFP |
735=f_u_vac |
        U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        220        2.20        2.20
          2 |      9,609       96.09       98.29
          9 |        171        1.71      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 5 May 2016