By making measurements of the scintillations of the 137-MHz beacon of ATS 3 at three sites along the 70°W meridian, it was possible to amass a data bank sufficient to obtain empirical analytical formulas of average scintillation at subauroral and auroral latitudes. The data base consisting of 15-min scintillation indices of 3–7 years of observations from Sagamore Hill, Massachusetts, Goose Bay, Labrador, and Narssarssuaq, Greenland, has been presented and discussed in a companion paper. Forcing functions for the empirical formulations are time of day, day of the year, magnetic index, and solar flux. The limitations of the data are outlined including single frequency of observations and the problem of limited excursion of scintillations. Corrections are given for geometrical effects using varying irregularity configurations.