When I was in school, one of the most agonizing periods was the time between taking an exam and getting it back. This strange, uncomfortable time would end in one of two ways. If I did well, it would generate a sort of positive momentum for my studies. On the other hand, if I did poorly, there would be an element of discouragement that weighed on my desire to engage. The U.S. economy submitted its July exam a few weeks ago; this week, we’ll get our first peek at whether the solid U.S. growth momentum seen in the second quarter carried over into the third, and what it might suggest for the broader trajectory of global growth.