Shares in Boeing Co (BA.N) slipped 2 percent on Tuesday after November deliveries suggested the world’s largest planemaker will need a surge in deliveries in December to hit its year-end targets, though it surpassed some analyst expectations.


Boeing said it delivered 61 of its top-selling 737 single-aisle jetliners in November, above its monthly production rate of 52, and higher than the 43 aircraft delivered in October.


While Boeing reports deliveries of specific airplane types but does not make comparable projections, Jefferies analyst Sheila Kahyaoglu said in a client note that Boeing would need to deliver 79 of its 737s in December to hit its total 2018 airplane delivery target of 810 to 815 airplanes.


“Our estimate assumes deliveries of the 737 reach 79 in December, which is unlikely,” Kahyaoglu said.


Boeing’s delivery data for 737s surpassed the expectations of some analysts. Before Tuesday, UBS analyst Myles Walton said Boeing delivered around 55 737s, while Baird’s Peter Arment said November 737 deliveries were roughly 45 aircraft.


Overall, Boeing deliveries for the first 11 months of 2018 rose to 704 aircraft from 680 in the same period a year earlier. That leaves 106 aircraft left to deliver to customers in December to meet its target.


Higher deliveries for the 737 and 767 were offset by drops in the 777 and its carbon-composite 787 Dreamliner, company data showed.


Investors and analysts closely watch the number of planes Boeing turns over to airlines and leasing firms for cues on the company’s cash flow and efficiency.


The November data suggests the Chicago-based planemaker may finally be getting a handle on supplier problems that have snarled production this year as it works toward even higher production rates next year.


“November deliveries showed nice lift in 737 MAX,” Cowen & Co analyst Cai von Rumohr said, adding: “this suggests production disruptions are largely out of the way.”


Airbus said last week it had delivered 673 aircraft up to the end of November, leaving 109 aircraft still to be delivered in December to reach a core target of 782 deliveries.


Boeing has said deliveries would rebound in the last two months of the year despite supply delays in engines from CFM International, a partnership between General Electric Co (GE.N) and France’s Safran SA (SAF.PA), and other components.


The company’s deliveries could take a hit if Indonesia’s Lion Air decides to cancel 737 MAX orders following a crash that killed 189 people in October.


Lion Air, a privately owned budget airline, has 190 Boeing jets worth $22 billion at list prices waiting to be delivered, on top of 197 already taken, making it one of the U.S. manufacturer’s biggest export customers.