Companies looking to boost their earnings-per-share by borrowing money to fund buybacks may want to consider another option: putting the money into their pension plans.

In a new report, Goldman Sachs Asset Management argues that the earnings boost from a pension contribution could actually be bigger than that received through share repurchases.

Companies have spent record amounts on buybacks over the past several years, often using using borrowed money to do so. Low interest rates have made the strategy appealing, as companies can issue debt relatively cheaply and boost their earnings in a low growth environment.

Stock buybacks for the first two quarters of this year totaled $289.1 billion for the first two quarters of the year. That’s ahead of last year’s pace, when buybacks hit a record $582.3 billion, according to Factset.

But low interest rates are a double-edged sword. While keeping borrowing costs down, they also increase pension obligations for companies offering defined benefit plans to employees. According to complicated actuarial math, the present day value of future pension liabilities increases as rates fall.

Consequently, S&P 1500 companies have struggled with obligations that have surged 36% this year alone, as of Sept. 30, totalling a combined $551 billion, according to Mercer. The deficit was $404 billion at the end of last year.

Meanwhile the cost of simply holding pensions on company books has increased in recent years. Congress has boosted the amount in premiums pension sponsors must pay to the Pension Benefit Guaranty Corp., the nation’s pension insurer. Businesses with underfunded plans, meaning the value of their assets don’t equal the liabilities, must pay added variable rate premiums that further increase the cost of their pensions.

Goldman’s analysis uses the hypothetical example of a company with earnings per share of $0.70. After borrowing $2 billion at a 5% rate and contributing the money to its pension, assuming a 6.5% return on its assets, the company would boost earnings per share by $0.0448 cents, compared to a $0.0337 boost through buybacks. The earnings boost includes assumptions for the tax deductibility of debt and the savings made by cutting the premiums paid to the PBGC. The report outlines the full analysis.

“We’re surprised we haven’t seen more of it,” said Michael Moran, pension strategist at Goldman Sachs Asset Management.

General Motors Co. and International Paper have both borrowed money to fund pension contributions this year.