Frequencies for first 10,000 rows of crosswalklevel variable in planxw2017 dataset :

  Crosswalk |
      Level |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      4,050       40.50       40.50
          1 |      3,751       37.51       78.01
          2 |      1,966       19.66       97.67
          3 |         85        0.85       98.52
          4 |        148        1.48      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Jun 2017