I still think that #1 sounds unnatural, but I do want to ammend my prior post.
You can include a time frame with "ever" in the context of an awaited event/thing, and it's used as intensifier.
Darn - we missed the goal again this month. No bonus for us.
I know. Do you think we'll ever get a bonus this year?
In your #1, it's the "ever" and the "decade" together that are the problem.
Fewer than half the people surveyed thought there would ever be a typhoon in Mongolia.