Delta Air Lines put slightly more passengers onto planes in 2012, which helps to boost its bottom line but also translates into more crowded aircraft cabins.

The Atlanta-based carrier’s planes averaged 83.7 percent full in 2012, up from 82.1 percent in 2011. Delta did that by cutting its flying by 1.8 percent while increasing its passenger traffic. Delta’s total passenger count in 2012 increased by 0.4 percent compared with the previous year.

Delta chief executive Richard Anderson told employees in a year-end memo that “we must continue our focus on courteous and helpful customer service” while improving on-time performance and other efforts. He said while many competing airlines are focusing on merger integration or restructuring, “2013 is a year for Delta to advance its position around the world.”