~ 12 - for mixed fission products at a year and a half is less, being about -1. 55). One use of the decline curveis to predict the level of activity of food items at somefuture date. For example, if the value for a food item was 100 on November 1, 1955 it would be 85 on January 1, 1956 and 56 on July 1, 1956, UNNERTY 40 UNIV. Gi L . - cies 7