SAN FRANCISCO — Lyft has chipped away at the market share held by its much larger ride-hailing rival Uber, at least when it comes to business travelers.

After notching very slight gains in the second through fourth quarters of 2016, Lyft's share jumped nearly 3 percentage points quarter-to-quarter in Q1 and Q2 of this year, from 7.7% at the end of 2016 to 9.8% in the first quarter, and to 12.5% in the second.

That's the same period in which Uber has been grappling with an incessant stream of issues ranging from charges of sexual discrimination to investigations into questionable business practices.

The data comes from a survey of business users' credit card spending out Thursday from expense management software company Certify, which analyzed data from 10 million receipts and expenses provided by 2,500 corporate clients.

Despite Lyft's improvement, Uber continues to have a dominant position in the U.S. ride hailing game, with 87.5% of the market, according to Certify.

Michael Goodwin, head of business development at Uber for Business, suggested that Certify's data likely was not a full picture of Uber's corporate business.

"We are seeing more organizations partner with us because we can provide a centralized bill, which eliminates the need for rides to flow through expense platforms in the first place," Goodwin told USA TODAY. "With centralized billing, companies can receive a single statement of all trips from the month and offer employees the smoothest possible experience."

Lyft also is pushing to woo business customers. Both Lyft and Uber have integrations with Certify; expense account processing is made easier when a traveler opts for an integrated partner.

"Our goal is to provide reliable, easy-to-adopt and cost effective transportation solutions to make Lyft the preferred partner for businesses," Lyft chief business officer David Baga told USA TODAY. "Integrating with expense management systems saves time and creates a seamless experience for employees to do their expenses.”

While Uber may have ceded some passengers to Lyft in recent quarters, it has still managed to grow largely by raiding businesses that used to be business traveler mainstays: rental cars and taxis.

When factoring in the losses to those transportation categories, Uber and Lyft both increased their share of the business transportation market by 2 percentage points last quarter, according to Certify data. Car rental share of the market dropped 2 percentage points to 29%, and taxis dropped 2 points to 8%.

"If you’re taxi provider, you’ve got to get a new game plan," says Certify CEO Robert Neveu.

Both Lyft and Uber are private companies that divulge little about their business operations. But Certify's numbers largely echo other reports that indicate that Uber has been giving up market share to its U.S. rival steadily since a rash of issues surfaced that caused some riders to delete Uber's app.

Uber has a market valuation of nearly $70 billion compared to Lyft's $7 billion. But while Lyft is focused on the U.S., Uber currently operates in more than 80 counties, and has recently had to give up on dreams of dominance in the Asian and Russian markets.

Follow USA TODAY tech reporter Marco della Cava @marcodellacava