Tables of the U.S. Standard Atmosphere 1962 were computed and tabulated up to only 90 km as functions of integer kilometer values of both geometric and geopotential altitudes. The geopotential tables have now been extended to 120 km altitude. This extension involved the development of an empirical function relating geopotential to geometric altitude. A discussion of this function along with limited geopotential tables was prepared for the U.S. Standard Atmosphere Supplements 1966. This function has also been used to prepare more extensive tables relating geopotential to geometric altitude and vice versa up to 10,000 km for latitudes from 0 to 90 degrees. In addition, a computer method was developed for automatically generating multilayer atmospheric models which rigorously fit arbitrary upper and lower boundary conditions.