Wallpaper comes in varied lengths and widths. In general, wallpaper is priced by the linear yard, or single rolls.
It can be packaged as double or triple roll bolts. Wall covering manufacturers do this to ensure more usable wallpaper from the same run and dye lot.
Commercial, wallcoverings are manufactured specifically for commercial use and come either 52 or 54 inches wide. They are sold by the linear yard. A lineal yard is the width of the roll (52″ or 54″) with a length of 36 inches (1 yard).