At first: I’m not sure if this is a bug or just an balancing problem.
When I release a MMO-game with a rating of 5.75 and develop (lets say every year) an expension pack (large) after a while (10-20 expansions) i sold about 30 billion units in total and every week about 300 million (which means an maintanace of $80billion and an income of $115billion).
So I think theres an exponential growth in units sold with every expension pack i release.
Greets
Thomas