Rising audit costs of the past few years have not yet leveled off, based on the latest data on audit fees, with companies reporting a 9.16-percent rise in audit costs from 2014 to 2015.

In the newest report on audit fees and non-audit fees from Audit Analytics, analysis through 2015 shows companies saw another increase in their external audit costs in 2015. Expressed as a factor of revenue, audit fees in 2015 for accelerated filers rose to $529 per million of revenue compared with $486 per million in revenue in 2014. And that figure was up from $475 per million in 2013 and $463 per million in 2012.