EU data is a good proxy for US and vice versa. We are all talking about sunspots no better than soothsaying regarding retirement, however the strongest sign still is that a product goes EOL in one of the markets. No better indicator of close EOL than that. If a product retires in one market you can bet that it will retire in the other one within a year in the worst case, but usually only within a few months.
Anybody in this game who disregards fluctuations of stocks in other markets as well as retirement neglects vital information from him- or herself, thus potentially making his or her investment decisions less profitable. In a market where information is the most valuable asset disregarding it is not the wisest to do, even if some pieces turn out eventually to be worthless because ignoring all of it leads to overlooking key data in the long run.
For example SSD went first in the US. Just assume the reverse scenario for a moment, that SSD went EOL in the EU first. Considering the US is still being the stronger market in terms of reselling activity, so the remaining stocks dry up faster, resulting a shorter time window for acting, which investor would have made more profits? The one who had jumped at EU EOL news and bought a stash at MSRP or the one who had waited out US EOL and bought at $600?