Arch Capital Group last night posted net income available to common shareholders for the second quarter of $171.5 million compared to $202.0 million for the same period in 2012.Arch said its second quarter results included losses for catastrophic events of $36.3 million, net of reinsurance and reinstatement premiums, primarily related to US tornado and hailstorm activity and flooding in Europe and Canada.The Company also reported after-tax operating income available to common shareholders of $135.0 million compared to after-tax operating income available to common shareholders of $141.4 million.“The Company's estimates for these events are based on currently available information derived from modelling techniques, industry assessments of exposure, preliminary claims information obtained from the Company's clients and brokers to date and a review of in-force contracts,” Arch said.The combined ratio was 87.4 percent compared to 87.2 percent.The company said the 2013 second quarter loss ratio reflected 1.5 points of current year catastrophic event activity, primarily related to US tornado and hailstorm events.Gross premiums written by the insurance segment in the 2013 second quarter were 4.1 percent higher than in the 2012 second quarter, while net premiums written were 8.0 percent higher than in the 2012 second quarter. Gross premiums written by the reinsurance segment in the 2013 second quarter were 10.4 percent lower than in the 2012 second quarter, while net premiums written were 13.1 percent lower than in the 2012 second quarter