CEMA is working on updating its Belt Conveyors for Bulk Materials and needs to develop an estimate of how books it might sell. I am interested in knowing how many copies of the DIN 22101 standard on the method of calculating belt conveyor horsepower that DIN sells in a year. "Information on other standards or conveyor design manuals would be helpful as well. CEMA would be willing to provide information on sales with other associations in exchange for their information.