XL Group has reported a net loss of $515.54m, or $1.62 diluted loss per share, for the fourth quarter of 2011, compared to a net income of $188.12m, or $0.57 diluted income per share, for the same period in 2010.

The net loss was for the quarter of 2011 was largely driven by a non-cash goodwill impairment charge of $429m.

The total revenues for the fourth quarter of 2011 rose to $1.73bn, compared to $1.59bn for the same period a year ago.

Operating net loss was $79.63m, or $0.25 loss per share, compared to an operating income of $242.43m, or $0.74 income per share, for the same period in the previous year.

Net investment income declined to $270.9m, compared to $290.4m in the prior year quarter.

Net premiums written in the property and casualty operations were $1.12bn where as net premiums earned were $1.39bn for the fourth quarter of 2011.

XL Group CEO Mike McGavick said that the company was clearly impacted in 2011, like companies throughout the property and casualty industry, by a year that suffered from one of the largest aggregate worldwide catastrophe losses in history, including, most recently, the devastating Thailand floods.