Luxmi wants to celebrate the birth of her first grandson by investing money for his future education. She estimates the annual cost of postsecondary education today to be $6,000 per year, and that the typical degree takes four years. She wants to invest a lump sum today that could sustain these payments with inflation starting 18 years from today. If annual inflation is 3.7%, and her investment can earn 6.6% compounded monthly, what amount does she need to invest today?