This graph below comes from a Wall Street Journal article A California Drought: Not Enough Children. It is talking about the impact of this dynamic:
... In 1970, six years after the end of the baby boom, children made up more than one-third of California's population. By 2030, they will account for just one-fifth, according to projections by lead author Dowell Myers, a USC demographer. "We have a massive replacement problem statewide," Mr. Myers said in an interview. ...
It is interesting to see how this dynamic is playing out nationwide.
