This is a currency note from the Bank of the United States and is not an obligation of the United States government. The Treasury Department did not issue notes intended for circulation as currency until 1862.
The grommet panel must be a minimum of 70 inches wide, between the side hem seams, to provide just slightly more than 1.5 times fullness on the 40-inch space.
Add the amount of desired overhang to that measurement if you want the roofing to hang over the eaves. Determine the roof's width. Divide the roof's width by 3. The result gives you the number of panels that you need. For a roof that is 45 feet (13.7 m) wide, you will need 15 metal panels. Panels come in a width of 3 feet (.91 m) each, but are cut to desired lengths.