Shares of AmTrust Financial Services plummeted to their lowest level in more than two years Monday after the company said it had discovered errors in its financial statements.

AmTrust also revealed that it had requested that the Securities and Exchange Commission grant it a 15-day extension to file its annual 10-K performance review, CNBC reported.

AmTrust, which specializes in insurance for small businesses, said it had found and corrected errors during the fourth quarter related to previous quarters in 201 and 2015, according to CNBC. The company found errors made when accounting for bonuses paid, foreign currency transactions and revenue associated with administrative services.

The revelations resulted in AmTrust’s shares taking an 18% plunge, hitting lows not seen since the end of 2014.

The company also reported Q4 earnings of 57 cents per share – missing by a fair distance the Thomson Reuters estimate of 74 cents. Total revenue was $1.42 billion, an 18% increase from the same period last year, according to CNBC.

Monday’s losses bring AmTrust shares down more than 17% for the year so far, while the S&P 500 has seen more than a 5% gain in the same period.