Table 1:

Sample characteristics, by birth order

Variable	First birth		Second birth
	M/%	SD	M/%	SD
Births	22.77		12.69
Time since first marriage/birth	3.55	1.06	7.08	6.76
Wife’s age	34.64	7.45	35.58	6.45
Husband’s age	37.43	8.79	38.08	6.98
Sex of first child (1=male)1	N/A		57.65
Region
Seoul	23.86		21.73
Metropolitan cities	26.12		28.04
Other areas	50.02		50.23
Wife’s socioeconomic status
Educational attainment
Less than high school	14.71		9.22
High school	33.83		38.93
Some college / junior college	21.03		24.25
University or more	30.43		27.60
Employment status
Standard employment	37.27		26.24
Nonstandard employment	7.27		6.78
Self-employment	13.67		10.73
Nonemployment	40.79		56.25
Husband’s socioeconomic status
Educational attainment
Less than high school	12.54		8.20
High school	26.56		33.22
Some college / junior college	23.12		21.54
University or more	37.79		37.04
Employment status
Standard employment	65.39		65.53
Nonstandard employment	6.53		6.69
Self-employment	20.64		21.74
Nonemployment	7.44		6.03
Household socioeconomic status
Annual income (logged)2	3.39	0.80	3.43	0.73
Homeownership
Homeowner	38.75		48.34
Jeonse (key money deposit)	42.79		37.69
Weolse (monthly rent)	11.97		10.03
Other	6.49		3.94
Person-year observations	2,297		7,938
Number of individuals	889		1,992

¹Dichotomous variable

²Annual household income is measured in 1,000,000 KRW, approximately 830 US dollars.