Table 1

Characteristics of Regional Greenhouse Gas Initiative (RGGI) states versus non-RGGI states in the USA, 2003–2014

All statesRGGI statesNon-RGGI statesP value*
GDP (Millions of US$), mean±SD275 019±3 63 987259 637±3 65 497278 087±3 62 3570.6509
Population (1000 of person), mean±SD5 813±69504 602±60176 067±71110.0603
Median household income (US$), mean±SD57 057±856063 801±780955 637±8024<0.001
Number of birth, mean±SD78 237±98 50556 620±77 03382 788±1 01 9420.0179
Birth weight (grams), mean±SD3 277±643 314±503 269±64<0.001
Birth rate of black babies, %15.69±2.8215.43±2.4315.74±2.890.3304
Mother’s education level, High school graduate or higher (%)81.32±7.5382.06±4.0481.17±6.940.2224
Number of hospitals, mean±SD97±8152±57106±82<0.001
Average temperature (°F), mean±SD52.46±9.3648.33±5.2453.33±9.80<0.001
  • *t-tests (or Wilcoxon rank-sum tests) for continuous data, Χ2 tests for proportions in categories.

  • RGGI, regional greenhouse gas initiative.