US commercial property insurance rates are expected to fall 10-15% across non-catastrophe-exposed and catastrophe-exposed risks, according to global broker Willis Group.

“Property rates have been falling for several consecutive quarters, and Willis does not see an end to this trend,” it says in its property and casualty market forecast.

Apart from the recent earthquake in California, this year’s loss experience has been “benign”.

The report says the influx of non-traditional capital to the reinsurance market remains steady, and is now pressing on the primary market.

Capacity remains abundant in commercial casualty lines, and Willis expects casualty rates to range from 10% lower to 10% higher.

Workers’ compensation rates could range from 5% lower to 5% higher, with rises of up to 8% in California, the report says.

In the aviation market, Willis forecasts rates will rise 20-30%, with large industry losses putting the brakes on several years of falling prices.

The stand-alone terrorism insurance market has gained capacity, which is driving down rates in low-risk zones.

But if Congress fails to extend the Terrorism Risk Insurance Act federal backstop, “rates could rise sharply”.