After almost a decade of negative interest rates, one of the world’s best-run pension industries is about to start guaranteeing clients a negative return.

It’s the latest sign that long-term subzero rates are forcing Denmark to reshape its finance industry. The country’s banks have already taken a world lead in imposing negative retail deposit rates, while Danish homeowners have access to mortgages at negative interest rates.

Denmark's pension industry, twice the size of its economy and ranked the best in the world alongside that of the Netherlands, is now taking another step into uncharted territory.

The Danish regulator has decided it’s no longer feasible for funds to promise savers in guaranteed-return products that they’ll get at least 1 percent. So from July 1, funds will only be allowed to guarantee savers minus 0.5 percent. (Savers opting for riskier pension plans that track market rates aren’t affected by the change.)

A negative return guarantee "is a weird concept," said Per Plougmand Bærtelsen, assistant director general at the FSA in Copenhagen. But that’s what savers need to accept, if they want to place their money into products "with zero risk, or low risk."

The decision may well accelerate a shift away from such guaranteed-return pensions in Denmark, which currently account for two-thirds of obligations to customers. The majority of premiums are now paid into products that are at the mercy of the market.

Many funds are also actively advising customers to switch to market-based products.

The last time the FSA changed the guarantee cap was back in 2011. It proposed lowering the limit in 2015, but then rates started to rise and the plan was shelved. Last year, the agency tried again, recommending a cap of zero, before this week settling on minus 0.5 percent. It applies to new policies and additional income existing customers earn.

The rate needs to be set at "a sufficiently prudent level," Bærtelsen said. Minus 0.5 percent may now be "below market developments, but you cannot rule out that in some periods the interest rates will fluctuate and can go below. We have seen that, and we have also seen that it has gone above again."

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