ProShare Advisors LLC is proposing a new trio of exchange-traded funds (ETFs) that would be used to bet against traditional retail, per Bloomberg.

Why it matters: Making money off America's floundering retail industry in America is "about the get a whole lot easier," as Bloomberg's Rachel Evans writes. Plus, there is reason to believe it would be lucrative — State Street's traditional retail ETF has lost more than 9% this year whereas an e-commerce ETF from Amplify has gained 30%.

How it would work: ETFs work like index funds to track a basket of assets, and are attractive to investors since their fees tend to be lower than those of mutual funds. One of the ProShare ETFs would short (i.e. bet against) shares of traditional retailers and go long on shares in companies that could benefit from increased e-commerce activity. The other two would use leverage to "boost the returns on their bets against the [traditional retail] industry."