I don't have a number with me. The thing I will point out is that it's certainly less than double the revenue cost of a $5,500 limit, given that only so many Canadians would take advantage of the difference in contribution room. It's also something that the revenue costs of the TFSAs will grow over time under a $5,500 limit, but that would be also the case, or a bit more of the case, under a $10,000 limit.
On October 18th, 2016. See this statement in context.