Chicago-based brokerage giant Aon Corp. announced that the results of its 2003 P/C earnings volatility study showed that insurers and reinsurers were more effective at minimizing earnings volatility last year. The study measures earnings volatility on a cumulative basis over the one-, two-, three- and five-year earnings periods ending Dec. 31, 2003, said the report. It covered more than 60 public companies within commercial lines, specialty lines, personal lines and reinsurance and concluded that solid underwriting and effective capital management are the key drivers to more predictable earnings. The leaders and runners-up were measured by sector and were measured over a period of up to 10 years. ACE, Hartford, Old Republic and AIG were noted as the least volatile overall. In specialty lines the least volatile were RLI and Baldwin & Lyons. Aon noted that on a year-over-year basis, earnings volatility for all of the companies included in the study, on average, was 18 percent lower than 2002. Earnings reflected solid underwriting results stemming from prior rate increases and only marginally higher catastrophe losses. On a relative basis, earnings volatility in 2003 was the lowest in personal lines in three of the four measurement periods compared with the other sectors, consistent with the results published last year.