Summary statistics for veh_aux dataset : by Jean Roth , jroth@nber.org , 18 Apr 2016 Variable | Obs Mean Std. Dev. Min Max -------------+--------------------------------------------------------- year | 56,820 1999 0 1999 1999 veh_no | 56,820 1.446815 .8470604 1 21 st_case | 56,820 278161 159484.4 10001 560162 a_body | 56,820 2.467881 2.064895 1 9 a_imp1 | 56,820 2.68578 1.354577 1 7 -------------+--------------------------------------------------------- a_imp2 | 56,820 2.776874 1.43413 1 7 a_vroll | 56,820 1.812249 .3905165 1 2 a_lic_s | 56,820 1.289282 .7274064 1 4 a_lic_c | 56,820 1.172439 .448523 1 3 a_cdl_s | 56,820 1.901285 .3825076 1 3 -------------+--------------------------------------------------------- a_mc_l_s | 56,820 3.879602 .5666379 1 4 a_spveh | 56,820 1.802429 .3981704 1 2 a_sbus | 56,820 2.994685 .1024519 1 3 a_mod_yr | 56,820 2113.887 983.2855 1920 9999 a_drdis | 56,820 1.929549 .2559071 1 2 -------------+--------------------------------------------------------- a_drdro | 56,820 1.975977 .1531226 1 2 by Jean Roth , jroth@nber.org , 18 Apr 2016