CREATE TABLE table_204_145 (id DECIMAL, "representative" TEXT, "state" TEXT, "district ( s ) " TEXT, "served" TEXT, "party" TEXT, "date of birth" TEXT, "date of death" TEXT, "age" TEXT)

how many of the listed senators were at least 90 years old when they died ?
SELECT COUNT("representative") FROM table_204_145 WHERE "age" >= 90
SELECT COUNT("representative") FROM "table_204_145" WHERE "age" >= 90