SeaTac more than doubled its download speed from last year, reaching 103 Mbps. Denver, which topped the list over the past two years, came in second at 78.7 Mbps. The slowest Wi-Fi speeds were in Toronto and Montreal, with download speeds of 7.1 and 6.4 Mbps, respectively, Ookla said. Both Canadian entrants improved on their speeds from 2017.

The data are from tests conducted on Speedtest.net from January-April 2018 by computers logged onto the airports’ Wi-Fi network. The ranking does not include airports that charge for Wi-Fi access.

Three major US hubs—Dallas-Fort Worth, Detroit and Miami—saw speed declines ranging from 26% to 59% over the past year, according to Ookla, with Detroit’s performance declining the most in the surveyed group. Dallas and Miami are hubs for American Airlines Group Inc., while Detroit is a hub for Delta Air Lines Inc.

The world’s busiest airport—and Delta’s largest hub—Hartsfield-Jackson Atlanta saw the largest one-year improvement in speed, jumping to 59.6 Mbps from 2.7 Mbps, according to the survey data.

LaGuardia fared the best of the three major New York-area airports, clocking a speed of 28.5 Mbps, good enough for 10th place on the list.