Ingenuity has surpassed expectations so far, but the martian winter can be harsh. 75% seems about right (maybe 85? not looked into specific failure points on a helicopter vs a rover)

Also plugging another Ingenuity market: 
https://manifold.markets/wasabipesto/will-ingenuity-have-more-than-90-mi

Close date is at the end of November to account for any margin between the end of Martian winter and the waking up of the helicopter. 

Will resolve to YES if the helicopter wakes up and make at least one successful flight, even if capabilities are somewhat degraded. Examples of acceptable deck rotation would be reduced flight time, damaged non-critical sensors, or reduced battery capacity. 

Will resolve to NO at market close if these conditions have not had a clear indication they will occur. For cases that fall in the middle, I will use my best judgment.

Jun 9, 5:02pm: degradation, not "deck rotation". Apologies