A really rough way to figure is that if it is 60" in diameter, you would need 2 pieces of 1 3/4" yards for front and same for back = 3 1/2 x's 2 = 7 yards. Now figure in the binding around the outside edge, up the slit and around the inside and that could be the other yard. I make and sell skirts and make a lot of them at 40" because I can do it at WOF. I sell a lot of them because people don't want to spend the money that a large one would cost (think they get a better deal at the dept. store!). You will end up with bits and bobs of the fabrics but, overall, it will be close to the 8 yards.