It is a fair point that for small negative changes you are getting a leverage effect (i.e. for a 1% down move in asset value you do have a 20% loss on your capi

It is a fair point that for small negative changes you are getting a leverage effect (i.e. for a 1% down move in asset value you do have a 20% loss on your capital). There is however a floor so the payout profile is a lot more like an option.