In North America, gradient is expressed in terms of the number of feet of rise per 100 feet of horizontal distance. Two examples: if a track rises 1 foot over a distance of 100 feet” ; a rise of 2 and-a-half feet would be a grade of “2.5 percent.” In other parts of the world, particularly Britain and places with heavy British influence, gradients are expressed in terms of the horizontal distance required to achieve a 1-foot rise. This system would term the above examples “1 in 100” and “1 in 40,” respectively.