A new tool has joined the growing list of mechanisms that cryptocurrency investors in the United States can use to speculate the price movements of bitcoin.

Bitcoin Market Predictor is the brainchild of Chicago-based company Level Trading Field. On its website, the company said the tool is “based on a very simple pari-mutuel system,” in which 10 people make a prediction on the future value of a publicly priced item—in this case, bitcoin—and the person with the most accurate prediction wins.

Bitcoin Market Predictor is aimed at retail investors, with each game costing $50 to play, according to the company. At the moment, Coinbase’s GDAX exchange is the only exchange that allows U.S. residents to short on bitcoin—although that feature is currently disabled while the GDAX reviews ethereum’s unusual price movements in June.

In an interview with CoinDesk, Level Trading Field CEO Lanre Sarumi said “there are really no tools available” that let retail investors to make the bet when they “believe the price is going to go down.”