A three-year slide in audit fees may be beginning to bottom out. Fees have been dropping for several years now, first as Sarbanes-Oxley work became more routine and then as companies scrutinized expenses in response to the economic crisis.

But a recent CFO analysis of audit and audit-related fees paid last year suggests that the trend has begun to slow. Only three of the top eight audit firms showed a drop in fees charged as a percentage of client revenue in 2009 (see "Firming Up" at the end of this article).

That's a marked change from an earlier CFO analysis that showed fees dropping dramatically from 2007 to 2008 for all but one (Crowe Horwath) of the top eight firms. (In both cases, the analysis by CFO included only ongoing engagements. Companies that changed auditors — an event that often results in lower fees — were not included.)

A separate analysis of all Securities and Exchange Commission–registered companies by CFO shows that, on average, most companies still saw their audit fees drop slightly last year (see "A Slowing Descent" at the end of this article). However, the drop was less pronounced than in 2008, and companies with revenues of more than $1 billion actually saw a sharp 9% increase.

As we reported in April (see "Auditing Your Auditor"), audit fees have been dropping across the board since 2007, and companies appear much more willing to change audit firms if the price is right. In 2004, more than a third of auditor changes were the result of audit firms walking away from clients. Last year, 82% of auditor changes resulted from companies firing their auditors (among the Big Four, the number was 90%). Companies aren't just negotiating lower fees; they have also been demanding more value — read "services" — covering everything from corporate-board education to competitive intelligence. Whether these latest figures presage a change that dynamic, or merely indicate that the most dramatic of the wheeling and dealing is now abating, remains to be seen.