The amateur Ektachrome series - Ektachrome, Elite, Elite II, Elite Chrome...diffs?

The amateur Ektachrome lineup has gone through everal revisions over the years.

Take Kodak ED-200: I've seen rolls labeled:
-Ektachrome ED-200
-Ektachrome Elite ED-200
-Ektachrome Elite II ED-200
-Elite Chrome ED-200

My question is, when were these different names implemented and what were the differences in each version. Also, what was the pro line equivalent to each?

Thanks!

No one knows???