Spirit Airlines Inc. (SAVE) has released its latest traffic report. The press release, available on Spirit’s website, includes figures for December and for 2016 as a whole.

In December, Spirit increased its revenue passenger miles by 12.5 percent. The airline flew 1.8 million paying passengers throughout the month compared to its 2.3 million available seats. The number of Spirit’s available seats was boosted by 16.6 percent in December because of 14 new routes introduced by the airline.

Because of the larger increase in available seat miles to revenue passenger miles, load factor at Spirit fell three points. As of Dec. 31, Spirit’s load factor was 80.3 percent. (See also: How can I use the load factor as an indicator for the profitability of the airline industry?)

For the entire 2016 year, Spirit reported positive growth of 19.9 percent in its revenue passenger miles. A nearly identical increase of 20 percent in available seat miles led to Spirit’s load factor remaining consistent at 84.7 percent.

In 2016, Spirit flew 21.6 million passengers with an average trip of 979 miles. The airline increased its total number of departures from 128,902 in 2015 to 149,514 in 2016.

Finally, Spirit reported its on-time performance rate for the month. On-time flights are those which arrive at the destination gate within 14 minutes of their scheduled arrival time. In December, Spirit arrived on time 73.3 percent of the time. Although the airline did not report its on-time performance rate for December 2015, the U.S. Department of Transportation Statistics says it was 68.75 percent.

Since January 2015, Spirit’s shares have increased by almost 50 percent. The airline is expected to release its fourth-quarter earnings on Feb. 14. (See also: Spirit Beats with Q3 Earnings.)