Investor Bill Ackman’s new closed-end fund made a poor debut on the New York Stock Exchange, with shares of Pershing Square USA falling 18% on the first day of trading Wednesday.

The shares of Pershing Square USA finished at $4o.90, down 18% from the IPO price of $50.

Ackman raised $5 billion in the deal, selling 100 million shares at $50 apiece in the first major U.S. closed-end fund in several years. A closed-end fund issues a fixed amount of shares, and then can trade at a discount or premium to its portfolio value.

Ackman offered fund buyers an inducement of stock in his management company, Pershing Square Inc. Buyers in the IPO got one share of the management company for every five shares of Pershing Square USA.

Shares of Pershing Square Inc ended trading at $24 on Wednesday. Pershing Square Inc. debuted in conjunction with the closed-end fund.

The sharp fall in Pershing Square USA stock means that those who participated in the IPO are in the red—even when considering the value of the Pershing Square Inc. stock that they received.

A buyer of five shares of the fund is now down $45 on an initial investment of $250, and has a share of Pershing Square Inc worth $24.

Barron’s wrote earlier Wednesday that Pershing Square USA could trade at a discount—which we estimated at close to 10%—for several reasons. These include a 2% annual fee, which is high relative to other those of other closed-end funds; a lack of natural buyers near the IPO price, given that investors in the deal got bonus shares; and the big discount of around 30% to portfolio value for Ackman’s European-listed closed-end fund, Pershing Square Holdings, that offers an alternative investment.

Ackman plans to buy high-quality growth stocks for the new fund. They are expected to be similar to those in the European fund, which holds such stocks as Alphabet, Amazon, and Uber Technologies.

Ackman appeared on CNBC and said his fund heralded a “rebirth” of the closed-end fund industry and that it was fundamentally different from other funds, due in part to his strong long-term record.

So far, Ackman’s fund is trading lower like closed-end funds historically have done. Investors will be watching to see if that changes in the coming weeks and months.