Summary statistics for veh_aux dataset : by Jean Roth , jroth@nber.org , 22 Oct 2016 Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- year | 45,960 2012 0 2012 2012 st_case | 45,960 280613 162306.2 10001 560113 veh_no | 45,960 1.429003 .8788085 1 31 a_body | 45,960 2.953046 2.319854 1 9 a_imp1 | 45,960 2.716253 1.422854 1 7 -------------+--------------------------------------------------------- a_imp2 | 0 a_vroll | 45,960 1.820344 .383905 1 2 a_lic_s | 45,960 1.488316 .9865358 1 4 a_lic_c | 45,960 1.186358 .4591459 1 3 a_cdl_s | 45,960 1.903764 .3812254 1 3 -------------+--------------------------------------------------------- a_mc_l_s | 45,960 3.694974 .8754907 1 4 a_spveh | 45,960 1.794735 .4038999 1 2 a_sbus | 45,960 2.995279 .0955931 1 3 a_mod_yr | 45,960 2158.781 1108.065 1926 9999 a_drdis | 45,960 1.964404 .1852831 1 2 -------------+--------------------------------------------------------- a_drdro | 45,960 1.983812 .1261994 1 2 by Jean Roth , jroth@nber.org , 22 Oct 2016