The Securities and Exchange Commission focused its comment letters in the most recent year on non-GAAP financial measures more than any other topic, surpassing even management discussion and analysis, the perennial favorite area of focus.

A detailed analysis by Deloitte of SEC comment letters on 2016 financial statement filings shows 43 percent of all SEC comment letters to public companies included remarks on the company’s use of financial measures that do not comply with Generally Accepted Accounting Principles. It was the most common concern raised in SEC comment letters for the year, with MD&A concerns addressed in 27 percent of remarks.

The SEC began in late 2015 calling out corporate uses of non-GAAP measures that run afoul of reporting rules. Companies are not prohibited from reporting performance metrics that fall outside of GAAP, but they must observe some guidance governing non-GAAP reporting to assure it does not outshine GAAP reporting.

While MD&A ranked behind GAAP in terms of the number of SEC comments in 2016, it still garnered plenty of staff attention, with comments focused on MD&A discussion on results of operations, critical accounting policies and estimates, liquidity, and contractual obligations, Deloitte reports. Behind those leading concerns, the SEC staff also commented on fair value, segment reporting, and revenue recognition, in that order of frequency.

Aside from the frequency of non-GAAP comments, the SEC comment letter trends were fairly consistent in 2016 with prior years, said Christine Davine, a partner at Deloitte. SEC staff have indicated they’ve seen some improvement in non-GAAP reporting compliance, so Davine said she expects trends to normalize in coming years. “I expect next year not to have non-GAAP measures as the number one area of comment,” she said. “I expect MD&A to resume its historic place.”

The comment letter analysis revealed a continued decline both in the number of reviews that led to comment letters and the number of comment letters issued. Those figures both have been falling steadily since at least 2013, Deloitte says. It also revealed the number of days it takes to complete a review and comment exchange has steadily declined, suggesting greater efficiency in the process, Davine said.

Both the filing process with preparers and the review process at the SEC have seen improvements over the years, says Davine. The SEC also has fewer companies to review as the number of public companies has declined, and it reviews far more companies than the number required under Sarbanes-Oxley.

Another factor, says Davine, is the relative stability of accounting standards the past few years. “There hasn’t been a major new standard to comment on,” she says. That will change in the coming few years as companies work to adopt new requirements on revenue recognition in 2018, followed by leases in 2019 and credit losses in 2020.