CREATE TABLE table_161591_2 (profit_before_taxation__s VARCHAR, operating_profit__s$m_ VARCHAR)

How many years was the operating profit (s$m) 717.1?
SELECT COUNT(profit_before_taxation__s) AS $m_ FROM table_161591_2 WHERE operating_profit__s$m_ = "717.1"
SELECT COUNT("profit_before_taxation__s") AS $m_ FROM "table_161591_2" WHERE "717.1" = "operating_profit__s$m_"