I'm having trouble understanding how Futures are worth more than Forwards when price and interest rates are positively correlated but both declining.
For instance, a Future with losses of -5 at T(n-1) and -5 at T(n) vs. a Forward with losses of -10 at T(n). How is the Future more valuable? Most textbooks I've read explain it as "losses derived from a falling futures price can be financed at a lower interest rate", but you're still having to borrow 5 at T(n-1) and paying back 5(1+r) at T(n). So total losses for the Future are 5+5(1+r) which is greater than 10 for the forward.