CREATE TABLE table_203_753 (id DECIMAL, "rank" DECIMAL, "name" TEXT, "caps" DECIMAL, "goals" DECIMAL, "years" TEXT)

how many players were playing in 1990 ?
SELECT COUNT("name") FROM table_203_753 WHERE "years" <= 1990 AND "years" >= 1990
SELECT COUNT("name") FROM "table_203_753" WHERE "years" <= 1990 AND "years" >= 1990