CREATE TABLE table_65243 ("Year" FLOAT, "Game" TEXT, "Genre" TEXT, "Platform ( s ) " TEXT, "Developer ( s ) " TEXT)

What is total number of years that has genre of first-person shooter?
SELECT SUM("Year") FROM table_65243 WHERE "Genre" = 'first-person shooter'
SELECT SUM("Year") FROM "table_65243" WHERE "Genre" = 'first-person shooter'