Sales of sneakers resulting from Yeezy’s collaboration with Adidas grew by 31 percent to nearly $1.7 billion in 2020, according to a document prepared by the Swiss bank UBS, details of which were reported by Bloomberg.

The partnership generated $191 million in royalties for Yeezy, the sneaker and apparel business of the American rapper Kanye West.

UBS said Yeezy’s sneaker business was growing at a “staggering clip,” in the document prepared this February, which placed a total value on the entire Yeezy business of $3.2 billion to $4.7 billion. The shoe deal with Adidas dates back to 2013 and features a string of limited-edition sneakers that routinely sell out.

The Swiss bank estimates that a new deal with retailer Gap could account for some $970 million of Yeezy’s overall valuation. That 10-year agreement focuses on clothing and excludes footwear as Yeezy’s partnership with Adidas in sneakers is set to run through 2026.