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.
Photograph: Corbis. US federal debt is still a record high. This week it passed a milestone: the fourth straight year the deficit has passed the $1tn mark. As of today, the national debt stands at $16,066,241,407,385.80 (just over $16 trillion).