Casualty rates climbed upward through the fourth quarter of 2012 and are positioned to continue the trend into 2013, a report from insurance-broker Marsh says.

In its “Benchmarking Trends: Casualty Rates Edging Upward” report, Marsh says the increases “are likely to be felt unevenly across the various industry sectors” and depend upon “client-specific risk factors.”

The report focused on four U.S. casualty lines: general liability, workers’ compensation, auto liability and umbrella/excess casualty.

Of the four lines, umbrella/excess saw the greatest percentage of clients experience increases (56 percent). Twenty-nine percent of clients in this line saw no change in rates, while 15 percent experienced decreases. The average increase for umbrella/excess was 4.9 percent in the fourth quarter, up from 3.2 percent in 2012’s third quarter.

Behind umbrella/excess, 54 percent of general liability clients experienced increases, 18 percent saw no change in rates, and 28 percent experienced decreases. The average rate increase was 2.1 percent.

Marsh notes that clients with “exceptionally good loss histories, strong safety controls, and lower hazard exposures generally continued to secure decreases at renewal.”

While terms and conditions for this line generally remained unchanged, “underwriting scrutiny” increased, which translated into longer processing times.

Turning to workers’ comp, 51 percent of clients experienced rate increases, 16 percent saw no change, and 33 percent experienced decreases. The average rate increase was 2.9 percent.

Marsh says this line of business has operated at a “historically unprofitable level for insurers.” Carriers sought to return to profitability through rate increases and higher retentions.

“Employers that favorably differentiated their claims management and loss control programs generally fared best, while those willing to take more control through loss sensitive programs tended to be more insulated from rate increases,” says Marsh.

Auto liability remained “relatively stable throughout 2012,” Marsh says, with the percentage clients seeing rate increases running in the 40s throughout the year. The percentage of clients experiencing increases was greatest in the fourth quarter (47 percent). Twenty-four percent had no change in rates while 30 percent received decreases. The average rate increase was 1.9 percent in the quarter.

Most insurers sought increases for this line, says Marsh, but typically agreed on rates were lower than the original quote.