Fewer Americans traveled by air over the Labor Day holiday weekend compared to the Fourth of July holiday just a few months ago, according to data from the Transportation Security Administration.

Just over 9.2 million people passed through TSA checkpoints from Sept. 2 through Sept. 6, according to the TSA — a noticeable drop from the Fourth of July holiday weekend when more than 10.1 million passengers traveled through U.S. airports. However, the number of Labor Day travelers was significantly more than Memorial Day weekend when the agency screened just over 7.1 million people.

The busiest travel day during this year's Labor Day holiday weekend was Friday when more than 2.1 million people took to the skies in the U.S. The slowest day was Saturday when only about 1.5 million people passed through airports.

The travel statistics represent about a 9.5% drop from 2019 when more than 10.2 million people passed through TSA checkpoints over the five-day Labor Day weekend.

Still, it was far more than the Labor Day holiday weekend last year when just under 4.2 million people traveled through U.S. airports over the same five-day period, according to the TSA's data.

The drop in travel demand comes as the highly contagious delta variant continues to spread and the director of the Centers for Disease Control and Prevention cautioned unvaccinated Americans against traveling ahead of the holiday weekend. In fact, more than 20% of surveyed Americans who initially planned to fly for the weekend canceled their flights due to concerns over rising cases and decided to drive instead, according to a poll from Cars.com.

Despite the slight drop in travel demand, Americans still packed beaches and college football stadiums, commemorating the unofficial end of summer. But the celebrations come amid the alarming increase in COVID-19 cases with daily recorded infections more than four times what the U.S. saw on Labor Day last year, USA Today reported.