Prices at April 1 reinsurance renewals varied widely according to geography and line of business, according to a new report released Thursday by reinsurance brokerage Guy Carpenter & Co. L.L.C., a unit of New York-based Marsh and McLennan Cos. Inc.

Prices rose throughout the Asia-Pacific region in response to the series of natural catastrophe losses sustained in the area during 2011, according to the report, “April 1 Reinsurance Renewals.”

“The largest catastrophes of the year—the Tohoku earthquake, the New Zealand earthquake and floods in Thailand and Australia—all occurred in the Asia-Pacific region,” according to the report. “These events had a significant impact on both primary insurers in the region and on global reinsurers.”

In Japan, earthquake excess of loss cover rose 10% to 40% and per-risk excess of loss cover rose 15% to 100%.

Even countries that were largely spared from direct catastrophe damage, such as South Korea, saw rates rise.

“Reinsurance rates in Korea were generally up 5% to 25% year over year on a risk-adjusted basis at the April 1, 2012, reinsurance renewal,” the report states. “Even though Korean catastrophe treaties were generally clean over the past 12 months, rates increased because of a general market hardening following the large number of insured losses across Asia.”

For the U.S. catastrophe market, the rate picture was mixed.

“For the U.S. property catastrophe reinsurance market, the number of programs renewing in April is much smaller than that renewing in January,” the report states. “Nonetheless, the range of average quotes at the April 1, 2012, renewal was almost exactly in line with the Jan. 1, 2012, spread at down 12% to up 11%.

Furthermore, individual company results vary substantially based on specific circumstances as the analysis of reinsurers becomes increasingly granular and tailored to specific risks, the report states.

“At April 1, 2012, the U.S. property-catastrophe reinsurance market continued to work through changes triggered by the RMS RiskLink v11 release and the catastrophe activity of 2011—and there was no ‘one-size-fits-all' answer,” the report states. “Reinsurers are becoming increasingly sophisticated in their approaches, and consequently gaining more confidence in their own risk assessment parameters.”

David Flandro, New York-based global head of business intelligence at Guy Carpenter, said overall capacity continues to be sufficient, and a comparatively mild disaster year thus far in 2012 bodes well for the industry.

“Despite the losses of 2011, the reinsurance sector continues to function normally, with sufficient capital to support the Asia-Pacific region and the global property/casualty insurance industry overall,” Mr. Flandro said in a statement. “Upward revisions to original loss estimates for some of the major 2011 catastrophe events continue to impact the industry. Fortunately, loss activity during the first three months of 2012 has been relatively light, with insured losses expected to be under $5 billion.”