The quantity of financial restatements from public companies has leveled off in the past four years and the severity of those restatements has remained low, according to a new report from the research firm Audit Analytics, but restatements have increased from accelerated filers for the third straight year.

During 2010, 157 accelerated filers—that is, issuers with a public float of at least $75 million—disclosed restatements, followed by 210 in 2011; 282 in 2012 and 290 in 2013, according to the report.

In 2013, revision restatements (restatements revealed in a periodic report without a prior 8-K, Item 4.02 disclosure that a company’s past financials can no longer be relied upon) represented about 68.8 percent of the restatements disclosed by 10-K filers. This percentage represents the highest percentage calculated since the disclosure requirement came into effect August 2004.

During 2013, the average income adjustment per restatement by publicly traded companies on the Amex, Nasdaq or NYSE markets was about $3.2 million, the lowest during the last seven years reviewed, according to Audit Analytics.

Last year, about 52.8 percent (or 235 out of 445) of the restatements disclosed by publicly traded companies (on Amex, Nasdaq or NYSE) had no impact on earnings, the highest during the last seven years reviewed.

The average restatement period was 548 days during 2013, the sixth year in a row with a period above but near 500 days.

Audit Analytics noted that the filing status designation is based on the company’s own disclosure to the Securities and Exchange Commission in the box it checks. After gaining an accelerated filer status, a company does not lose the designation unless it drops below $50 million in float. The report doesn't distinguish between accelerated filers with a public float of between $75 million and $700 million, and the SEC designation of "large accelerated filers" with a float of $700 million or more.