Socioeconomic data: Some great global graphics over time in Max Roser’s “Our World in Data” site.
Child stunting: A good summary of the latest UNICEF-WHO-World Bank estimates of child malnutrition across the world can be found here. In 2016, nearly one quarter of all children under 5 were deemed to be stunted. That is over 150 million. Thankfully the count is falling but it is still far too high. As EOP Chapters 7 and 8 explains, in addition to the short term welfare losses to these kids and their families, stunting has longer-term costs in learning and adult productivity that help perpetuate poverty.
Health inequalities in the US: Average life expectancy (LE) at birth is 79 years, but the range across US counties is huge as shown in this study, which is also summarized here. There is a 20 years gap between the county with the highest LE (Summit County Colorado with 87 years LE) and that with the lowest (Oglala Lakota County, South Dakota, home to the Pine Ridge Native American reservation). This is about the same as the LE gap between Japan and Sudan!