Fig. 1. Line Graph. From Centers for Disease Control and Prevention. Hamilton BE, Martin JA, Ventura SJ. Births: Preliminary data for 2010. National Vital Statistics Reports, 2011; 60(2): Table S-2.* Hamilton BE, Martin JA, Ventura SJ. Births: Preliminary data for 2011. National Vital Statistics Reports. 2012; 61(5). Table 2, Hyattsville, MD: National Center for Health Statistics, 2012.