Oil has surged 20 percent this month to $57 a barrel as expanding violence in Yemen stoked concern that supplies could be disrupted.
The rally follows the biggest drop since 2008, with crude falling as low as $43.46 a barrel in March, as a price war broke out between OPEC producers and U.S. shale drillers. West Texas Intermediate oil, the U.S. benchmark, is now back up at close to a four-month high. Prices gained in each of the last six weeks, the longest stretch in more than a year.
Before deciding prices will race back to $100, here are five charts worth keeping in mind.
"The cart is moving ahead of the horse," Barclays Plc analysts said in an April 27 report.
Long-dated futures are falling
Even as prices rise for oil contracts that will be settled in the next few months, the price of oil is actually falling when delivery won't take place for years.
For example: two months ago, crude oil for delivery in January 2019 sold for $68.32 a barrel, according to New York Mercantile Exchange data. Monday, the same contract traded at $66.35.
That could indicate that traders are betting the near-term rally has overshot.
U.S. stockpiles are at an all-time high
The U.S. has almost 500 million barrels of crude oil in storage. That's by far the most oil in storage since record-keeping began in 1982.
Supplies have grown because of surging domestic production and restrictions on most crude exports.
Heard of the 'fracklog'?
Companies have already drilled thousands of wells and are waiting for prices to recover before they start pumping. That could quickly flood the market with fresh supplies, capping the rally.
The three top-producing shale fields have more than 3,400 drilled but uncompleted wells, according to Bloomberg Intelligence. In oil-producing regions nationwide, there are more than 4,000.
Saudi Arabia keeps on pumping
The Saudis sent the market into a freefall in November when they decided to defend their market share instead of propping up prices, and they show no sign of changing course.
The kingdom's output was close to an all-time high in March, according to the International Energy Agency, and Prince Abdulaziz bin Salman, the deputy oil minister, said on April 27 that the market is in "excellent" condition.
The Organization of Petroleum Exporting Countries next meets in June.
Producers are locking in prices now for oil produced later
Producers, merchants and other industry participants are selling futures and options contracts that will lock in future profits, ensuring they can keep pumping, data from the U.S. Commodity Futures Trading Commission show. Such so-called short positions are the highest since October 2011. That could be a sign of drillers locking in a future price now because they might not get a better one.