Units of paper quantity the 500-sheet ream has become the de facto international standard. A paper bundle is a quantity of sheets of paper, currently standardized as 1,000 sheets. A bundle consists of 2 reams or 40 quires. As an old UK and US measure, it was previously equal to 960 sheets. When referring to chipboard, there are two standards in the US. In general, a package of approximately 50 pounds of chipboard is called a bundle. Thus, a bundle of 22 point chipboard (0.022" thick) 24" × 38", with each sheet weighing 0.556 pounds, contains 90 sheets. However, chipboard sold in size 11"
Paper size a number of different sizes were defined for large sheets of paper, and paper sizes were defined by the sheet name and the number of times it had been folded. Thus a full sheet of "royal" paper was 25 × 20 inches, and "royal octavo" was this size folded three times, so as to make eight sheets, and was thus 10 × inches. Imperial sizes were used in the United Kingdom and its territories. These sizes are no longer commonly used since the UK switched to ISO sizes. Many of these sizes were only used for making books (see bookbinding),