CREATE TABLE table_79197 ("Year" FLOAT, "Date" TEXT, "Location" TEXT, "Winner" TEXT, "Loser" TEXT, "Weight class" TEXT)

How many years were lightweight class on february 28, 2009?
SELECT COUNT("Year") FROM table_79197 WHERE "Weight class" = 'lightweight' AND "Date" = 'february 28, 2009'
SELECT COUNT("Year") FROM "table_79197" WHERE "Date" = 'february 28, 2009' AND "Weight class" = 'lightweight'