CREATE TABLE table_50415 ("City" TEXT, "State" TEXT, "2010 population" TEXT, "Peak population  ( year ) " TEXT, "Numeric decline from peak population" TEXT, "Percent decline from peak population" TEXT)

what is the numeric decline from peak population when the perfect decline from peak population is -16.76%
SELECT "Numeric decline from peak population" FROM table_50415 WHERE "Percent decline from peak population" = '-16.76%'
SELECT "Numeric decline from peak population" FROM "table_50415" WHERE "Percent decline from peak population" = '-16.76%'