Table 2:

Summary Statistics by Sample

	All Births	Residences within 2.5 km of well			T-Stat
		Total	Before	After	for difference
Characteristics of birth
Birth weight (grams)	3321	3340	3343.23	3310.30	2.70**
Term birth weight (grams)	3407	3415	3418.39	3383.15	3.30***
Gestation in weeks	38.77	38.76	38.76	38.71	1.33
Premature	0.08	0.08	0.076	0.077	−0.09
Low birth weight (LBW)	0.07	0.06	0.055	0.063	−1.52
Small for gestational age (SGA)	0.11	0.10	0.098	0.106	−1.25
APGAR 5 minute	8.81	8.89	8.886	8.885	0.07
Female	0.49	0.49	0.485	0.495	−0.95
Mother’s Characteristics
Drop Out	0.164	0.113	0.112	0.118	−0.88
High School	0.270	0.296	0.297	0.288	0.93
Some college	0.260	0.299	0.299	0.293	0.64
College plus	0.298	0.290	0.289	0.299	−1.07
Teen Mom	0.057	0.048	0.047	0.049	−0.34
Mom Aged 19–24	0.265	0.268	0.267	0.274	−0.65
Mom Aged 25–34	0.527	0.547	0.545	0.559	−1.31
Mom Aged 35 and older	0.150	0.137	0.140	0.117	3.03**
Mom Black	0.156	0.025	0.025	0.024	0.15
Mom Hispanic	0.092	0.011	0.011	0.010	0.57
Married at time of birth	0.575	0.632	0.633	0.626	0.71
Mom Smoked While Pregnant	0.227	0.299	0.299	0.300	−0.13
Received WIC	0.385	0.398	0.395	0.427	−2.94**
Medicaid	0.272	0.326	0.320	0.376	−5.45***
Private Insurance	0.576	0.567	0.569	0.549	1.84
Wells within 2.5 km
# of wells before birth	0.000	0.333	0.000	2.89	−19.30***
# of wells during gestation	0.000	0.188	0.000	1.714	−93.13***
Observations	1098884	21610	19246	2364

Notes: The samples described here include only singleton births.

Significance:

*p<0.10,

^**p<0.05,

^***p<0.01.