US national debt

As the US national debt has grown—from a quaint 6 trillion dollars to a rather less quaint 31 trillion—more pedestrians have been struck by cars, a correlation that invites the interpretation that government spending literally runs people over. The coefficient is 0.866 across twenty-one years, during which both metrics climbed with the inexorable confidence of things that politicians promise to address and never do. The debt ceiling rises, the pedestrians fall, and the chart treats both with equal mathematical composure.

The US national debt grew from about 6 trillion in 2002 to over 31 trillion by 2022, driven by tax cuts, military spending, entitlement growth, and the pandemic relief packages that added roughly 5 trillion in a single year. Pedestrian fatalities grew from about 4,800 to over 7,500 during the same period. Both metrics are monotonically increasing and both correlate with GDP growth—a wealthier nation generates more debt and more traffic simultaneously. The connection is not causal but economic: the same expanding economy that produces tax revenue (and the deficit spending that supplements it) also puts more vehicles on more roads in more urban areas where pedestrians walk.

Twenty-one years of debt and pedestrian deaths rising together is a reminder that in a growing economy, everything trends upward: spending, borrowing, driving, walking, and dying. The debt is national, the fatalities are local, and the correlation between them is simply the sound of a country getting bigger in every measurable dimension. The budget is unbalanced. The crosswalk is unprotected. Both will continue.