1. The U.S. unemployment level fell to 3.9 percent — the lowest since 2000.

April marked the 91st consecutive month of job gains, the longest streak of increases on record. But that has not led to higher wages, and experts aren’t quite sure why.

Another important caveat: The statistic does not include people who have given up looking for work. And the unemployment rate for black Americans hovers well above the rate for white Americans.

Just a few years ago, getting to an unemployment rate below 4 percent seemed impossible, our economics correspondent wrote, adding, “There are benefits, for economic policymakers and everyone else, to staying open-minded about what is possible.” Above, the New York Stock Exchange.