Right back at you. I was also commenting on rate rather than saying that I saw one or 2 in the last 10-15 years.
Not all locations are the same though, so maybe there has been a noticeable decrease where you're at. Personally, I think I've felt an increase if anything.
These changes aren't always easy to spot. I live in a city that acquired a significant Ukrainian population over the last two years. Whenever I see a group of kids that biked to an arbitrary location and play, they turn out to be young Ukrainians. They do the exact thing local kids would do 20 years ago.
Not all locations are the same though, so maybe there has been a noticeable decrease where you're at. Personally, I think I've felt an increase if anything.