The U.S. Atlas of Nuclear Fallout 1951-1970 (Volume 5 of the series) details the math behind the values found in volumes 1-4. Broadly, the total fallout values and radioisotope values were calculated from ratios associated with a set of documents known as the Hicks Tables. These tables, compiled by Dr. Harry Hicks and published by the Lawrence Livermore National Laboratory, discuss radioisotope values for each of the major aboveground nuclear tests. In 1997 the National Cancer Institute published the results of a 15-year study titled, Estimated Exposures and Thyroid Doses Received by the American People from Iodine-131 in Fallout Following Nevada Atmospheric Nuclear Bomb Tests. While the data was limited only to a single radioisotope, iodine-131, the Hicks Tables allowed estimates to be calculated for both total fallout and over 60 radioisotopes. The mathematical procedures associated with these estimates are found in this volume. The volume also includes an error propagation analysis by Dr. Stelu Deaconu of the University of Alabama’s Propulsion Laboratory.