Facebook said it is getting better at measuring advertising performance in the wake of Apple’s limits on sharing data on iPhones.

On Monday, Meta, the company formerly known as Facebook, presented new guidance to brands, saying that its ad platform is more accurately counting conversions, even as it still runs into bugs that could affect individual advertisers.

Last year, Facebook told its more than 10 million advertisers that it was “underreporting” conversion by an average of 15%, but now after implementing new tools the average underreporting is closer to 8%, according to a blog post from Meta's director of ads product marketing Goksu Nebol-Perlman. 

“As we continue to build ad solutions that can do more with less data, we expect some level of underreporting will remain as part of our baseline,” Nebol-Perlman said.

Advertisers still encounter some underreporting problems. Last week, Meta uncovered another bug that undercounted conversions for some web and app campaigns, Nebol-Perlman said. “The changes we made to resolve the issue improved the measurement for affected metrics,” Nebol-Perlman said. 

A conversion is one of the most basic advertising measurements that tells a marketer when a consumer viewed an ad and then took an action like downloading an app or filling up a digital shopping cart. Facebook and Instagram, like so many apps in Apple’s ecosystem, were cut off from watching consumers who did not opt into being tracked. That made it more difficult to identify a consumer who saw an ad on Facebook apps and then converted on an advertiser’s website.

The app-tracking restrictions have made it more difficult, especially for prolific app advertisers, which promote games, delivery services and other product to mobile devices. The major apps like Facebook, Snapchat, TikTok, Pinterest and Twitter have had to work within Apple’s new measurement ecosystem to apply more limited, but more private, results to advertisers.

Apple’s changes particularly hit Facebook, because it is the largest social media ad platform. Last month, while reporting fourth-quarter earnings, Meta forecast an ad sales slowdown, growing between 3% and 11% in the first quarter this year. “With Apple’s iOS changes and new regulation in Europe, there’s a clear trend where less data is available to deliver personalized ads,” Meta CEO Mark Zuckerberg said during the earnings call last month. “But people still want to see relevant ads, and businesses still want to reach the right customers. So we’re rebuilding a lot of our ads infrastructure so we can continue to grow and deliver high-quality personalized ads.”

On Monday, Meta’s ads team outlined the new tools that are being used to keep its ad platform humming. Facebook has been encouraging advertisers to plug into its conversion API—application programming interface—that facilitates communication between the marketers and Meta.

Facebook also is adopting more automation and artificial intelligence that it hopes will improve advertising performance. There are new automated app campaigns, for instance. “Our internal tests showed that Automated App Ads saw a median 6% lower cost per install and a median 9% lower cost per action than a manual app install campaign setup,” Nebol-Perlman’s blog post said.