Note: As Mike Yassa, the lead author on the study, pointed out to me, the study did not actually test whether consuming caffeine before a task enhances memory, the problem being that other confounding factors can then lead to difference in performances on the test.
The US debt is more than $20.1 trillion, the largest in the world. Here are the 3 reasons it grew so large, and how it damages U.S. economic growth. The US debt is more than $20.1 trillion, the largest in the world.
WORLD WAR II. The debt-to-GDP ratio hit its all-time record of 113% by war's end. Debt was at $241.86 billion in 1946, about $2.87 trillion in current dollars. Unlike after World War I, the US never really tried to pay down much of the debt it incurred during World War II.Still the debt shrank in significance as the US economy grew.HE ROAD TO $16 TRILLION. Because on top of the roughly $11.4 trillion in US government debt, which can be bought and sold and is floating around in financial markets, there's also nearly $5 trillion in debt that the US government owes to itself.