I know that the most recent Bureau of Labor Statistics report found the lowest level of black unemployment in nearly half a century, as noted by the editors of the Wall Street Journal in a recent editorial. But I don’t know why and, unfortunately, neither the BLS nor the editors give me much help there. Here’s what the editors imply:
The jobless rate for blacks has always been substantially higher than for whites, and it tends to fall faster later in the economic cycle as growth picks up steam.
which I find neither convincing nor encouraging.
Why has the black jobless rate fallen? The generally low jobless rate? Faster job growth? Decreased Mexican immigration? Greater mobility? Lower black labor force participation rate? More discouraged workers? All of the above? Some of the above? Something else?

The graph at the top of the page, from the St. Louis Fed, illustrates the black unemployment rate. The graph above from the same source illustrates the black labor force participation rate. When the LFPR decreases, the number of discouraged workers who, consequently, vanish from the unemployment statistics, tends to increase.
Prison overcrowding.