A typical income is the dollar/hr that is most obtainable - it is the pay for jobs that most people can apply to and get.

It used to be a rate of pay that young people could start a family on. In the 1990s I could answer an ad for a job that most people could do. That job alone would be nearly enough to support wife, me, 2 young kids. I'd make up the diff on the side.

That's gone and birth rates can't climb without it.