As indicated by Eq. 1 or Eq. 2, a single exponential relationship was used to model the decline of radioactivity in diet items. Use of these equations led to an estimate of the dietary removal rate constant, k, over the entire residency interval. The average per cent decrease in the yearly activity ingested was determined from this dietary rate constant as follows: 2 = 100 (l-e ~Ck+h) ty (3) where % = average per cent decline in the atom ingestion rate during the residence interval. The definitions of the other quantities in Eq. 3 were the same as previously given. The value of t was taken as 365 days and the % reflected the average yearly decline averaged throughout the interval over which a nuclide was observed in people. Thus for 1376, the average was for a period of 24 years at Rongelap and 27 years at Utirik. In the development of the three equations several assumptions were made. For instance, decay of nuclides which were absorbed during transit through the stomach and small intestine was assumed to be negligible relative to their decay within the systemic organs. This was because of the long half-life of the nu- clides relative to the transit time through the upper portion of the gastrointes~ tinal tract. Urine activity and body-burden data were assumed to represent in- stantaneous values rather than incremental values. This was because the sam- pling periods for whole-body counting and urine collection were very short relative to the intake period. Additionally, one liter or 24 hour urine samples (which ever was less) were collected. This reduced the influence of biological variation of activity concentration between morning and evening voids. Since