According to a new research paper out of the Carroll School of Management at Boston College, more than half of startups that run ICOs (“initial coin offerings”) fail within four months of the ICO.

And yet, total ICO fundraising in 2018 so far has already nearly tripled the total from 2017, according to CoinDesk’s ICO tracker. ICOs in 2018 so far have raised almost $14 billion, compared to $5 billion raised in 2017. The total number of ICOs this year has also already eclipsed last year’s total (394 to 343), only halfway through the year.

Neither stat should come as a shock to anyone who has been paying attention to this exploding fundraising method. But taken together, the Boston College study and the fundraising data offer a dual reminder: ICOs are extremely risky investments, and crypto investors don’t appear to care. (It’s important to note that most registered ICOs are only open to accredited investors, a bar that starts at $200,000 in annual salary or a net worth of $1 million.)

In an initial coin offering or “token sale,” a tech startup (mostly cryptocurrency or blockchain startups, but not always) creates a digital token intended for later use in the company’s ecosystem, and sells the tokens to buyers in an auction. Buyers typically pay for the new token with existing cryptocurrencies, usually ether or bitcoin. Ether is the token of the Ethereum blockchain, which was designed to execute “smart contracts” and thus has become the go-to method for token sales.

Many media outlets have compared ICOs to IPOs, but that is misleading. While an ICO is a way to raise capital and circumvent traditional VC firms, it is not at all like a public offering.

When you buy tokens in an ICO, you get no ownership stake or voting rights in the company. The tokens are not akin to shares. There is no guarantee that the token you’re buying in an ICO will accrue value, and there is no guarantee that the company itself will even exist after the ICO.

The Boston College study confirms that: 56% of the new startups that offer ICOs cease to exist four months after the ICO. The very title of the study labels ICOs, “digital tulips.”

The best return on investment for buyers is to sell the tokens off in the first three months, the authors of the study tell Bloomberg.

But the returns have also been getting worse recently, the study finds, even as the volume of ICOs, and the average amount raised in them, have increased.

In other words: more crypto companies are going the ICO route, and they are raising more money by doing it, but investors are typically losing unless they monitor the price of their tokens daily and time the coin market just right to cash out before the company vanishes.