Suzy's Candy Distributors has an annual demand for its boxes of "Chocolate Heaven Candies" of 250,000 units, an ordering cost of $85 per order, and an annual holding cost percentage of 16%. The current purchase price for each box is $28, but the supplier has notified Suzy that starting next week, the purchase price will rise to $40. Suzy's inventory of boxes is about to be depleted. How many boxes should Suzy purchase?