Table 1.

Descriptive statistics.

Variable	2012		2015
	Mean	Standard Deviation	Mean	Standard Deviation
Internet use	1.22	0.785	1.35	0.934
Self-rated health	3.01	1.053	3.18	1.062
Physical health	3.42	1.217	3.45	1.117
Mental health	3.73	1.038	3.72	0.927
Individual cognitive ability	2.06	0.607	2.09	0.607
Gender	0.56	0.497	0.49	0.500
Age	69.10	7.209	69.39	7.469
Marital status	0.73	0.444	0.74	0.436
Household income	43,072.49	269,983.171	61,361.82	380,656.167
Education level	2.40	1.276	2.39	1.263
N	2821	2821	3185	3185