By Carlos Pallordet

LONDON, Aug 18 (Reuters) - The North American insurance composite, compiled by investment banks Stonybrook Capital and Weild & Co, outpaced the S&P 500 and Nasdaq-100 with a 1.5% rise, while all 12 industry groups advancing in the week.

The S&P rose 0.9% in the week to Friday while the Nasdaq-100 added 0.4%.

The Dow Jones industrial average increased by 1.7%.

Meanwhile, the small cap Russell 2000 index added 3.1% in the week, moving into positive territory on a year-to-date basis.

Stonybrook-Weild highlighted the mixed nature of inflation reports revealed in the week, with the Consumer Price Index $(CPI.UK)$ reassuringly steady at 2.7%, below expectations, but the Producer Price Index $(PPI)$, coming in well above expectations.

Following the release of the former on Tuesday, the investment banks said: “the market applauded, with investors increasing their expectations of further 2025 rate cuts from one to three”.

However, according to Stonybrook-Weild, sentiment shifted on Thursday as the Producer Price Index report showed the benchmark, which is the Fed’s favoured measure of inflation, surged to 0.9% against the 0.2% economists had forecast.

“Investors still fear that businesses will start to push tariff increases along to consumers”, the investment banks said.

“Renewed inflation would put greater pressure on the Fed: Economists had overwhelmingly been calling for rate cuts to support growth and employment. But if inflation is disappointing, the Fed may have to toe the line on rates,” they concluded.

In the North American insurance composite, advancers led decliners by 88 to 24.

The two best-performing groups were micro cap insurers, up 6.3%, and title insurers, up 2.7%.

The group of global P&C carriers was also among the best performing in the week, rising 2.5%.

This followed a fall of 1.3% in the previous week.

Berkshire Hathaway led the gains in the cohort, with shares adding 2.8%.

AIG rose 2.4% while Chubb increased by 1.1%.

Standard commercial insurers were up 1%, while specialty commercial insurers rose 0.8%.

Among the latter, Ambac, Assurant and Hamilton Insurance Group saw the largest rises, with shares up 15.9%, 4.5% and 4.3%, respectively.

Intact Financial, the largest company in the cohort by market capitalization, shed 0.3%.

Arch Capital rose 2.1% while WR Berkley and Markel added 0.2% and 0.9% respectively.

In contrast, shares in Aspen and Fidelis fell 3.2% and 3.0% respectively, while Axis Capital was down 1.2%.

Meanwhile, reinsurers were the worst performing group in the composite, eking out a gain of only 0.2%.

Leader Everest Group rose 0.6%, while Reinsurance Group of America, the second largest company in the cohort by market capitalization, added 0.9%.

In contrast, Conduit Holdings fell 8.5% in the week, followed by Greenlight Capital which was down 2.2%.

Shares in RenaissanceRe slid 0.6%.

Meanwhile, global brokers were up 1.0% for the week.

Marsh McLennan was the highest riser in the cohort, with shares up 1.7%, followed by AJ Gallagher which increased 1.1%.

WTW and Aon, were up 0.8% and 0.2% respectively.

The Stonybrook-Weild North American Insurance composite is up 3.6% on a year-to-date basis.

In this article, we have included a selection of industry comp tables published in full by Stonybrook and Weild & Co in their weekly update.