Vol 3 page 329 solution 3

I have trouble understanding the 2nd bullet point in solution number 3 - where did this formula come from? Can’t we just plug and chug the futures position increase in value BPV F *change in yield+number of futures contracts?



That’s what you’re doing. (Well, except for the “+”, which I assume is a typo, and that you meant “×”.)

Am I missing something?