It seems to me that to truly judge the full financial impact of CWA '09 one would have to be God or at least omniscient to sort through all the factors. One could add up the lost payments from the congregations that left, that would tell part of the story. One could also look at congregations that have sharply reduced giving and investigate why (division in the congregation, diversion of funds in protest, major industry leaving town, knock down drag out fight between two matriarchs in the Women's Guild, etc.). Now you are asking for a lot of work. God would know but His accounting department does not release figures.
Has there been an effect? That seems very, very likely. What is the extent - hard to determine. Importance - of greater importance is whether the decision was in line with what God has told us in His word, and in line with God's will for His church. There is a whole other debate. Ultimately, if it was God's will that it be decided the way it was, the financial cost is secondary - part of the cost of doing God's business which is at times high - ask the original disciples. If it was not God's will, even if there would have been a financial benefit, it should not have been done.
What is God's will in the matter? Now there is a topic for discussion.
Dan