Slope is typically measured two different ways. Earthen slopes adjacent to roadways are expressed as the lengths in V:H, where the numbers are factored out to reduce the V to 1. For example, if a measurement is 2 units vertical to 12 units horizontal, the measurement is expressed 1V:6H. Shoulder side slopes are typically less steep than earthen slopes by about an order of magnitude. These are measured by taking the rise and dividing it by the run, and expressing it in terms of percent. For example, a 4 inch drop in 100 inches is calculated by 4/100, or 4 percent.