Table 1.

Descriptive statistics.

Variable	Obs	Mean	Std. Dev.	Min	Max
HQDRT	144	0.125	0.140	0.015	0.641
UDTL	144	0.197	0.134	0.025	0.796
LED	144	6.668	0.925	5.328	8.748
DGI	144	5.332	0.707	4.060	7.058
PD	144	14.637	0.727	13.444	16.209
DOFT	144	0.113	0.160	0.001	0.815
IS	144	0.717	0.129	0.501	0.964