As popular oil ETF plunged to single digits, retail investors rushed to buy the dip

• When popular oil ETF USO plunged to single digits as oil prices turned negative earlier this week, retail investors piled into the ETF, trying to catch the bottom.
• Over the course of six weeks, data from Robintrack.net shows a 2,050% increase in Robinhood accounts that own the ETF. During that same time, USO plunged 70%.
• On the other side of the trade were the shorts, who've reaped more than $300 million in gains amid the oil carnage.
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Since the start of an oil price war between Russia and OPEC began in early March, retail investors piled into popular oil ETF USO, trying to catch the bottom and make a profit.

Data from Robintrack.net, a website that tracks how many Robinhood accounts own a particular stock, shows a 2,050% increase in Robinhood accounts that own USO over the past six weeks.

On March 9, when USO was trading at $8.73, there were 8,677 accounts that owned the oil ETF. Fast forward to April 23, and there were 186,573 Robinhood accounts invested in the ETF. Over that same time period, USO has fallen 70%.

During that six-week period, oil prices went negative for the first time ever, USO announced an 8-1 reverse split, and OPEC began to consider steep oil production cuts to stop the plunge in prices.

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On the opposite side of the long USO trade were the shorts, who reaped almost $300 million in profits since the plunge in oil prices began.

The situation recalls a popular investing phrase: Don't try to catch a falling knife.