The mega retailer, which has claimed the top spot on the Fortune 500 for the past 13 years, has increased its number of in-house truck drivers by 33% over the past three years in part thanks to better wages and benefits.

In 2022, it boosted drivers’ starting pay to around $115,000 from an average salary of $87,000 previously. At the high end, drivers can make $135,000 per year, according to a Walmart spokesperson. The 2024 median pay for heavy and tractor-trailer truck drivers was $57,440 per year, according to the Bureau of Labor Statistics. 

Apart from a pay increase, Walmart also uses technology that allows for more reliable schedules compared to other companies. While some in the trucking industry are away for weeks at a time, Walmart gives its drivers consecutive days off of work and assigns them regional delivery territories to allow them to be home every week, a Walmart spokesperson told Fortune.

These perks, along with the better-than-average pay, have increasingly helped the company expand its pool of drivers and include more women. Just 9.5% of truck drivers in the U.S. are women as of 2024, according to the Women in Trucking Index—that’s compared to an estimated 18% of drivers at Walmart, according to a study by workforce intelligence company Revelio Labs that was viewed by Fortune. Bloomberg first reported on the study.

Through a 12-week training program that helps store associates transition to the trucking industry, Walmart has also increased its number of women drivers, a spokesperson said. Around 1,000 people have gone through the program, Bloomberg reported, representing about half of the company’s new drivers.

Possibly due to its efforts, Walmart has a five percentage point oversupply of truck drivers compared to its demand, according to the study by Revelio Labs. 

Walmart’s efforts to bring in more drivers, including those with less experience, is pivotal as the broader trucking industry faces a driver shortage that is expected to bring a shortfall of 160,000 drivers by 2028, according to the American Trucking Association. The broader category of U.S. retail, currently faces a shortfall of drivers, with demand for drivers exceeding supply by seven percentage points, according to Revelio Labs.

Older truck drivers are retiring and younger people aren’t keen to jump into trucking partly due to the long hours and time away from home. A 1,000-person survey from heavy-duty truck parts company FinditParts found that a quarter of Americans would not become truck drivers no matter what pay they were offered. 

For Walmart, any disadvantage in its supply chain, including a driver shortfall, could put it at a disadvantage with Amazon, with which it has been increasingly competing with in recent years, especially with its Walmart+ membership.

Without enough drivers, supply chains are delayed and prices go up. Finding and retaining drivers is thus of the utmost importance for companies like Walmart, Paul Bingham, a director of transportation consulting at S&P Global Market Intelligence, told Bloomberg.

“Trucking companies will need more drivers,” he said. “and they’ll have to attract them from the non-traditional population cohorts.”