CREATE TABLE table_5115 ("Year" FLOAT, "Class" TEXT, "Team" TEXT, "Points" FLOAT, "Rank" TEXT, "Wins" FLOAT)

What was the last year that they had less than 16 points in class 500cc?
SELECT MAX("Year") FROM table_5115 WHERE "Points" < '16' AND "Class" = '500cc'
SELECT MAX("Year") FROM "table_5115" WHERE "Class" = '500cc' AND "Points" < '16'