Table 4.

Decomposition Analysis of Concentration Index in CES-D Score

Variable	Elasticity	Ck	Absolute Contribution to C	Percentage Contribution to C
Age
60–69	Ref
70–79	−0.0094	−0.0938	0.0009	−5.61
≥ 80	−0.0072	−0.0717	0.0005	−3.26
Gender
Female	Ref
Male	−0.0454	0.0610	−0.0028	17.55
Marital Status
Divorced or else	Ref
Married	−0.0383	0.0108	−0.0004	2.61
Educational Attainment
Primary school and below	Ref
Junior high school	−0.0116	0.1455	−0.0017	10.67
Senior high school	−0.0018	0.1790	−0.0003	2.07
Higher education	−0.0019	0.1629	−0.0003	1.99
Household income	−0.0821	0.1315	−0.0108	68.41
Health Insurance
Without health insurance	Ref
Covered by health insurance	−0.0062	0.0022	0.00001	0.09
Geographic Location
Living in eastern region	Ref
Living in central region	0.0155	0.0385	0.0006	−3.78
Living in western region	0.0111	0.0011	0.00001	−0.08
Residency Location
Living in rural area	Ref
Living in urban area	−0.0199	0.0514	−0.0010	6.49
Smoking
No	Ref
Yes	−0.0009	0.0226	−0.00002	0.12
Drinking
No	Ref
Yes	−0.0080	0.0530	−0.0004	2.68
Social Interaction
No	Ref
Yes	−0.0276	−0.0050	0.0001	−0.87

Notes: C_k indicates the concentration index of each explanatory variable; C stands for the concentration index of each independent variable; Ref represents the reference group.