Insurers are showing no signs of slowing their aggressive pricing, with commercial rates taking another dive in the past six months, according to the latest broker survey.

Brokers responding to the survey, which is compiled by the National Insurance Brokers Association (NIBA) after the December 30 and June 30 renewals periods, expressed concerns over the long-time viability of the insurer price wars.

The mid-year survey shows price cuts across all classes of business insurance. But personal lines appear to be bucking the trend, with domestic rates stabilising and even hardening.

NIBA CEO Noel Pettersen says brokers have reported a continued softening of the commercial lines market, due to underwriters lowering premiums to be more competitive.

"Despite consolidation of the industry brokers are finding it increasingly easy to obtain quotes, even for hard-to-place risks, via electronic quoting applications," Mr Pettersen said.

The NIBA survey shows 77% of brokers reported falls in premiums for commercial clients, compared with 19% who said there had been no change and 5% who experienced increases. In December, 60% reported drops in premiums, while 65% reported falls in June last year.

When asked to rate the hardness of the commercial lines market on a sliding scale from one to 10 - one being the softest and 10 the hardest - brokers sided with a softer market. More than 70% of respondents reported the market being at least a "four" while 22% described the market as a "two".

Amid the frantic bidding and counter-bidding from insurers, brokers are also concerned recent reductions were not sustainable, with more brokers reporting "irrational decreases" in premiums.

"This is of some concern, with some brokers reporting huge rate reductions from various underwriters trying to increase and hold market share," Mr Pettersen said.

"We absolutely believe that competition is good for our clients, but we don't want to see the industry return to any unsafe patterns of behaviour when it comes to pricing."

When asked to rate the hardness of the personal lines market on the same sliding scale, the majority of brokers (39%) described the market as hard. In the December 2006 renewal period only 27% of respondents rated the market at this level.

Brokers also identified compliance costs as a major issue, with 40% of them spending $16,000 to $30,000 every year.

More than one in five (21%) respondents spend $11,000 to $15,000 per year and a further 20% spend $31,000 to $45,000 on regulatory costs. Some respondents (14%) are spending $71,000 to $100,000 complying with regulation, and 3% of companies are spending more than $100,000 on compliance.