A new analysis of recent Public Company Accounting Oversight Board inspections suggests corporate auditors are continuing to struggle to keep up with the uptick in mergers and acquisitions following the financial crisis.

Consulting firm Acuitas reports in its 2015 Survey of Fair Value Audit Deficiencies that 49% of Fair Value Measurement (FVM) audit deficiencies in 2013 were attributable to mergers and acquisitions activity, up from 45% in 2012 and an average of 9% from 2008 to 2011.

Errors ranged from failing to properly test data on cash-flow projections and improperly testing management’s techniques for valuing assets, to sometimes failing to detect intangible assets that needed to be assigned a value.

“We have seen a significant shift from the years where FVM deficiencies were largely the result of financial instruments to the current trend of business combinations and a failure to test or understand financial assumptions,” Mark Zyla, managing director of Acuitas, said in a news release.

“This shift has likely been caused by audit improvements for financial instruments that resulted from the PCAOB inspection process and by increased merger activity in recent years,” he explained.

Overall, according to the survey, 43% of all audits inspected by the PCAOB in 2013 had deficiencies (compared with 16% in 2009), with FVM and impairment deficiencies representing 31% of those deficiencies.

The number of FVM deficiencies caused solely by failures to assess risk and test internal controls also remained high in 2013, at 45% of all deficiencies for the top 25 firms. By comparison, such failures were present in 22% of FVM deficiencies between 2008 and 2012.

“The auditing community should certainly be concerned about the continuing increase in deficiencies caused by a failure to assess risk and internal controls, and the PCAOB’s assessment that they are caused by ‘a lack of due professional care,’” Zyla said.