There have been other studies like this done in other parts of the world, they all have come to similar conclusions. Here was one conducted in Germany from 1990-2017:

https://journals.plos.org/plosone/article?id=10.1371/journal...

Here's another one that shows a significant decline in Puerto Rico:

https://www.pnas.org/doi/full/10.1073/pnas.1722477115