CREATE TABLE table_24543 ("Year" FLOAT, "Horse" TEXT, "Driver" TEXT, "Trainer" TEXT, "Country of owner" TEXT, "Odds of winner" TEXT, "Winning time  ( km rate ) " TEXT)

When were the odds of winner 16.66?
SELECT "Year" FROM table_24543 WHERE "Odds of winner" = '16.66'
SELECT "Year" FROM "table_24543" WHERE "Odds of winner" = '16.66'