I was looking for something else in the old PADI Training Bulletins and found this information:
1996 EANx first offered. Prerequisites were AOW or OW plus 10 logged dives. 2 OW dives were required.
2000 Prerequisites of AOW/10 dives dropped.
2004 DISCOVER EANx offered; 32% maximum, no dives required.
2006 the 2 dive requirement dropped.
2009 Computer-based version of course offered.
1996 EANx first offered. Prerequisites were AOW or OW plus 10 logged dives. 2 OW dives were required.
2000 Prerequisites of AOW/10 dives dropped.
2004 DISCOVER EANx offered; 32% maximum, no dives required.
2006 the 2 dive requirement dropped.
2009 Computer-based version of course offered.