Comparing model for model doesn't tell you anything. It could be, for example, that the CJ3 took sales away from the 300. I've no idea but your simpletons view shows nothing.
However perhaps people prefer the new phenom to the rehashed CJ. Maintenance wise it's excellent. Though no where near the amount of service centres that cessna has in Europe. Though in turn they seem to be starting to vanish.
If I were a gambling man I wouldn't bet against Embraer domination in the light and mid size sector for a few years ahead.