In an effort to capture the large jet market, Hiro Airplanes invested $11.264 billion developing its B490, which is capable of carrying 840 passengers. The plane has a list price of $276.5 million. In discussing the plane, Hiro Airplanes stated that the company would break even when 253 B490s were sold. Assume the break-even sales figure given is the cash flow break-even. Suppose the sales of the B490 last for only 12 years. How many airplanes must Hiro sell per year to provide its shareholders a rate of return of 17 percent on this investment?