Wall Street Journal:

It’s hard to tease out all the factors driving this trend, but one is probably migration to, and employment growth in, the Sunbelt and right-to-work states. The Supreme Court’s 2018 ruling in Janus held that public workers who refuse to join the union can’t be forced to pay “fair share fees,” providing an added economic incentive to opt out, though there is no huge jolt in the trend line.

It’s still worth keeping the hard figures in mind, since union membership drives inevitably make splashy headlines when they target brands such as Starbucks. For all of that organizing activity, not to mention President Biden’s four years of being “the most pro-union President in history,” the shrinking of Big Labor hasn’t stopped.