 swung by about 91%. I'll use the API to get more sig figs.

Includes resolutions even if no one corrected the market beforehand.

Does not include any market with less than 10 traders at the time of the swing. Does not include any market with a structure designed to make this happen. (Like the creator offering to pay back all the traders or something like that.) Does not include someone spiking the market and it being corrected shortly afterwards. Does not include incorrect resolutions. Only includes binary markets.

I'll defer to Isaac to resolve any ambiguous cases.