Summary statistics for nmimpair dataset :

by Jean Roth , jroth@nber.org , 18 Apr 2016

    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
       state |        143          43           0         43         43
     st_case |        143    430166.5     99.7066     430003     430336
      veh_no |        143           0           0          0          0
      per_no |        143     1.41958    1.406287          1         10
    nmimpair |        143           0           0          0          0

by Jean Roth , jroth@nber.org , 18 Apr 2016