Public transit sits within Transportation & Logistics, moving everything else on this list — the connective tissue of physical trade, a category with a real, though adjacent, scale: $417B/year in transport investment needed through 2030 in lower- and middle-income countries alone; transport reaches up to 12% of GDP in many of those economies and employs roughly 200 million people worldwide — not a single global market-size figure (World Bank). Unlike 10 of the category's 20 items, public transit has no institutional comparative tracker — this is one of 10 items in Transportation & Logistics that stay editorial judgment rather than institutionally sourced.
Public transit is 1 of 20 items in Transportation & Logistics. See the full ranked list, or browse all 20 Human Endeavors categories.