Waymo, the robotaxi unit owned by Alphabet, has crossed 450,000 weekly paid rides, according to a letter from investor Tiger Global viewed by CNBC.

That’s almost double the milestone it hit in April, when Waymo reported 250,000 paid robotaxi rides a week in the U.S.

“Waymo is the clear leader in autonomous driving, recently surpassing 450k trips per week with a product that is 10x safer than human drivers,” Tiger Global wrote in a letter to investors announcing the launch of a new fund.

Waymo is one of the largest positions in Tiger’s 2024 fund.

This year, Waymo has also announced a slew of expansions, including its debut on freeways in three cities, and autonomous driving in cities including Miami, Dallas, Houston, San Antonio and Orlando.

The latest milestone is also another sign that Waymo is continuing to push ahead of self-driving competitor Tesla, which has run limited pilots in Austin and the Bay Area.

According to Tesla’s latest earnings call, executives said the company hit a quarter of a million miles with its fleet in Austin, and more than one million in the Bay Area. In July, Waymo announced 100 million total fully autonomous miles.