Frequencies for first 10,000 rows of mtran variable in natl2013 dataset :

     Mother |
Transferred |
RFP 571=? R |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,030       90.30       90.30
          U |        145        1.45       91.75
          Y |        825        8.25      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015