A fund manager has a well-diversified portfolio that mirrors the performance of the S&P 500 and is worth $450 million. The value of the S&P 500 is 1,250 and the portfolio manager would like to buy insurance against a reduction of more than 6% in the value of the portfolio over the next six months. The risk-free interest rate is 5% per annum. The dividend yield on both the portfolio and the S&P 500 is 2.5%, and the volatility of the index is 25% per annum. If the fund manager buys traded European put options, how much would be the insurance cost?