I'd also like to exit, but am sitting on a...

I'd also like to exit, but am sitting on a not-insignificant (IMO) loss. A large part of me wants to hold for 1-2 months in search of vindication, but perhaps not if the cost of carry is likely to exceed that. Is there any rough rule of thumb for calculating the capital depreciation of holding? (Appreciate the current volatility may simply mean no).