United came in second place on this list.
Viral videos showing a United Airlines passenger dragged off an overbooked plane on Sunday are still making waves, as the airline’s stock price tumbled on Tuesday. The ugly episode left us wondering: Which airlines are most (and least) likely to overbook flights in the first place?
A study released recently by MileCards.com shows that in 2016 Delta was the airline most likely to give passengers compensation due to overbooked flights. The airline paid out some form of compensation—usually flight vouchers or credits—to 10 passengers out of every 10,000. United was second on the list, with compensation given to 7.2 out of every 10,000 passengers, followed by Southwest (5.9), Spirit (5.4), American (4.1), Virgin America (3.0), Alaska (2.9), Frontier (1.4), and JetBlue (0.5).
So it looks like JetBlue Airways—named one of MONEY’s best airlines in our 2017 travel report—is the carrier least likely to be overbooked.
But the MileCards.com data above focuses only on voluntary bumps, in which passengers agree to miss a flight in exchange for some compensation. It doesn’t include involuntary bumps like those that occurred on United’s flight over the weekend.
According to the Department of Transportation, a total of 40,629 passengers were denied boarding involuntarily on domestic flights in 2016. That may sound like a lot, but it’s a decline from 2015, when 43,704 passengers were bumped involuntarily. The airline with the most involuntary bumps last year was America’s biggest domestic carrier, Southwest, with 14,979. Southwest also had one of the highest rates of involuntary bumps—0.99 for every 10,000 passengers, second only to the regional puddle-jumper carrier ExpressJet (1.51).
JetBlue actually had a relatively high involuntary bump rate—0.92 per 10,000 passengers, ninth highest out of America’s top 12 airlines. This is because while JetBlue appears to overbook flights less often than others, when there were overbookings it was more likely to bump passengers against their will rather than offer compensation to those missing flights voluntarily. In 2016, JetBlue gave compensation for 1,705 voluntary bumps, while involuntarily bumping 3,176 passengers. (All things considered, 2016 could have been a fluke for JetBlue: The year before, it denied boarding involuntarily to only 73 passengers, for the lowest rate of any airline, 0.02 per 10,000 passengers.)
Delta, on the other hand, may overbook flights the most, but it’s also the most likely to pay off passengers to convince them to get bumped voluntarily. The airline gave compensation for a staggering 129,825 voluntary bumps in 2016, while involuntarily bumping only 1,238 passengers. Hawaiian Airlines had the lowest overall rate of involuntary bumps in 2016, at 0.05 per 10,000 passengers, followed by Delta (0.1), Virgin America (0.12), Alaska (0.4), and United (0.43).
Take note that passengers who are denied boarding due to overbooking must receive compensation per federal regulations: The airline must pay 400% of the customer’s one-way fare, up to a maximum of $1,350, if the passenger is delayed to his or her final destination by more than two hours for flights within the U.S.
The good news, as the MileCards.com study reveals, is that it appears fewer passengers are being denied boarding against their will:
The bad news is that the overbooking of flights is still common practice within the industry: A total of roughly 475,000 passengers were denied boarding voluntarily or involuntarily last year because the airlines sold more tickets than there were seats on the plane. And, as the fiasco on a United flight this past weekend demonstrated, when there are overbookings the airlines are allowed to choose who gets kicked off the plane and have them removed—forcibly if necessary.
This story originally appeared on Money.com.