Toxic releases. The Environmental Protection Agency requires industry to report releases of any of a list of toxic chemicals. The total amounts released

(in thousands of pounds) were 3,006,577 in 1988, 1,736,461 in 1998, and 1,265,879 in 2005. Give an index number for toxic chemical releases in each of these years, with 1988 as the base period. By what percentage did releases increase or decrease between 1988 and 2005?