The best operating frequency (f) is a balance between the competing requirements of licensing, good backscattered power, which goes as 1/f 2, and favors a lower frequency, and the reflection height, which goes as f, and favors a higher frequency.
In all, $73.75 billion in licensed goods were sold last year.
It monitors factories in dozens of countries, including Bangladesh, Honduras and Vietnam, that produce licensed goods with university logos.
Many fans already have plenty of licensed goods, so the leagues are constantly searching for products to reach new audiences.
By comparison, apparel (including hats) and footwear make up 32 percent of the N.B.A. income from licensed goods.
Nearly half of the N.F.L.'s income from licensed goods comes from apparel and headwear, according to Ira Mayer, the editor of The Licensing Letter, an industry newsletter.
The biggest challenge in selling licensed goods is from counterfeiters who flood the Internet with knockoffs that end up on online auction sites like eBay.
Mayer said there were risks for Nike, most notably the threat of a work stoppage, which would drastically cut into sales of licensed goods.
In doing so, workers producing University licensed goods are expected to work in humane and safe conditions and receive fair wages.
Novelties like the M.L.B.-licensed caskets (and urns, which sell for $799), by contrast, comprise less than 5 percent of the total retail sales of the league's licensed goods.
