CREATE TABLE table_8846 ("Year" FLOAT, "Ship" TEXT, "Departed From" TEXT, "Departed On" TEXT, "Returned On" TEXT)

From how many years did tampa, FL depart?
SELECT SUM("Year") FROM table_8846 WHERE "Departed From" = 'tampa, fl'
SELECT SUM("Year") FROM "table_8846" WHERE "Departed From" = 'tampa, fl'