WestJet's 93.2 percent on-time arrival rate ranked it as May's most punctual major North American airline,

according to FlightStats. On average, 81.6 percent of North American carriers’ May flights arrived at their gates within 15 minutes of their scheduled times. Among the 12 largest carriers, Alaska Airlines (89.4 percent), Delta Air Lines (86.2 percent), JetBlue Airways (85.7 percent) and Air Canada (85.3 percent) also had above-average on-time arrival rates. US Airways (81.5 percent), Southwest Airlines (79.4 percent), American Airlines (78.3 percent), United Airlines (77.7 percent), Virgin America (77.1 percent), Frontier Airlines (74.6 percent) and Spirit Airlines (63.9 percent) were below average.