Things really took off for Delta Airlines in 2019. The fourth quarter of last year was one of record earnings, surpassing expectations. They also flew by their competitors to become the world’s biggest airline.

One component of Delta’s success was the unfortunate story of the grounded Boeing 737 Max fleets, which only affected Delta’s competitors, American, United and Southwest, never having purchased those suspicious airplanes. As a result, Delta could grab 7.5% revenue growth, partially due to better efficiency. One important airline metric, revenue per available seat mile (RASM) was up by 2.4%.

When Delta is high, so are its employees. The company is going to pay its 90,000 workers their highest ever profit-sharing bonus: $1.6 billion. That comes out to about 16.66% of each employee’s yearly salary, or about 2 months’ worth of pay.

“2019 was the best year in our history,” CEO Ed Bastian said. “These results simply would not be possible without the incredible work of our Delta team.”

The company was smart as well as lucky in 2019. Avoiding the Boing 737 Max could have been a combination of luck and smarts; while avoiding angry labor disputes was certainly smart. Having good weather at their hubs, of course, is simple luck.