Boston-based insurer Safety Insurance Group has reported first-quarter net income of $11.8 million, compared to $19 million for the comparable 2008 period – a 37.9 percent decrease.

On May 5, the board of directors approved and declared a quarterly cash dividend of $0.40 per share on the issued and outstanding common stock, payable June 15 to shareholders of record June 1.

Safety paid $0.40 per share in dividends to investors during both first quarters ended March 31, 2009 and 2008. Safety paid $1.60 per share in dividends to investors during the year ended Dec. 31, 2008.

The company said it continues to hold no subprime mortgage debt securities. All mortgage-backed securities were either government or agency guaranteed or are rated Aaa/AAA. As of March 31, the company said it maintained $98.6 million in short-term securities, cash and cash equivalents and has no outstanding debt.

The loss experienced was primarily a result of a decrease in personal automobile average earned premiums per exposure, Safety said in a statement.