Fertility Crash: Negative Mood, the Vaxx or Both?

Two tweets I saw passed around thsi weekend looked at Germany's and the Netherlands' drop in fertility.

Unless there is a vaxx and unvaxxed control group, the drop could be mainly driven by social mood. If mood is driving it, the drop will accelerate around August or September (mapping to the stock market peak rather than vaccinations) and continue sliding for at least six months.

Here are the Germany and Netherlands country ETFs. They peakedin May and August 2021, respectively.