For U.S. IPOs, 2017 has been the year of the flop. Blue Apron has tanked since it started trading last month. Shares of Snap fetch less than $15, the lowest since its debut in March. And the Bloomberg U.S. IPO index has risen just 1.5 percent this year, underperforming the S&P 500's 10 percent gain. What's going on? Bloomberg IPO reporter Alex Barinka joins host Alex Sherman to explain the lackluster performance of Blue Apron and Snap, and how MuleSoft and Canada Goose have avoided the same fate.