BBUS, page-2401

Thanks, I understand how the fund moves and apologies if my question wasn't clear. My "DYOR" understanding is that the fund purchases futures contracts to generate the inverse return you have kindly pointed out to me, targeting IIRC a 200 to 275% return. When those contracts fall outside that target range, my understanding was that the fund needs to purchase new futures using OUR capital to restore the target ratio thereby creating what I have described as capital "decay". My question was simply whether there is a rough rule of thumb to calculate when that decay occurs and by how much, relative to the movement in the SP500 futures quote.

It seems crosek has pointed me in a useful direction. Thanks anyway.