Zurich Insurance Group AG, Switzerland’s biggest insurer, will cut costs by more than planned as it seeks to reverse a drop in earnings.

Chief Executive Officer Martin Senn said he will make additional annual savings of at least $1 billion by the end of 2018, including $300 million by the end of next year.

Zurich will save about $600 million from shared services, human resources, finance and communications, he said in a phone interview from Switzerland’s financial capital on Thursday. It is too early to comment on possible staff reductions, he said.

Europe’s insurance executives are seeking ways to bolster earnings as they grapple with a slump in interest rates on the debt they have purchased, spurred by the European Central Bank’s bond-buying program. Zurich has cut about 670 jobs and started selling underperforming businesses to help lower costs.

Senn said the company will reduce costs at the general insurance unit, which sells property and casualty policies, by about $200 million by the end of 2016. Expenses as a proportion of premium income at the division increased to 30.5 percent last year from 29.7 percent in 2013.

Zurich reported on May 7 that first-quarter profit fell 4 percent to $1.22 billion, the third-straight quarterly decline. Profit from general insurance, a business headed by Mike Kerner, slid 20 percent to $706 million.

Costs Rose

Zurich’s costs, excluding its Farmers unit in the U.S. and restructuring charges, rose to $10.1 billion last year from $9.5 billion in 2013, partly as a result of “complex middle-office processes and systems” and too many employees in high-cost locations. The expenses included $2.9 billion for support functions, which rose from $2.7 billion, and for information technology, which climbed $200 million to $2 billion, according to a company presentation.

Senn says he will cut costs to help reach a target for return on equity, a key measure of profitability, of 12 percent to 14 percent by the end of 2016. It fell to 11.1 percent in 2014 from 11.6 percent the previous year.

To reach the cost savings, Zurich will incur about $400 million to $600 million in accounting and restructuring charges, with the majority included in this year’s results.

The company reiterated a plan to redeploy $3 billion of excess capital by the end of 2016. The cash will be either spent on mergers and acquisitions or a return of capital to shareholders, it said.

Chief Financial Officer George Quinn told analysts earlier this month that Zurich had “the shorthand of $3 billion” in capital available.

The shares rose 0.7 percent to 305.80 Swiss francs at 12:33 p.m. in Zurich, valuing the company at 46 billion francs ($49 billion). They declined 1.9 percent francs this year compared with a 15 percent gain for the Bloomberg Europe 500 Insurance Index.