(Bloomberg News) Policy makers are robbing savers by driving down real interest rates as they keep borrowing costs at record lows in a "devil's bargain," Pacific Investment Management Co.'s Bill Gross said in a commentary.

"Central banks and policy makers are taking money from one class of asset holders and giving it to another," Gross wrote in an investment outlook posted on the firm's website. "A low or negative real interest rate for an 'extended period of time' is the most devilish of all policy tools. And the asset class holder that it affects, or better yet, infects, is the small saver and institutions such as insurance companies and pension funds."

The difference between the yield on 10-year Treasury notes and the year-over-year consumer price index, known as the real yield, was 1.90% today, down from an average of 2.62% since 1991. It narrowed from a high of 5.95% in August 2009 as the Federal Reserve has kept the benchmark interest rate in a range of zero to 0.25% to spur economic growth.

The drop in real 10-year interest rates has "arguably been responsible" for gains in the stock market and 2% to 3% annual appreciation in bonds, Newport Beach, Calif.-based Gross wrote. At the same time, it has lowered the returns of small savers and investors in long-term fixed-income assets, he wrote.

"The metaphorical devil's bargain has its equivalent in the credit markets these days," Gross wrote. " To put it bluntly, they are robbing savers and taking money surreptitiously from longer-term asset holders who are incorrectly measuring future inflation," he wrote.

Reducing Holdings

Gross said investors may want to reduce holdings of Treasuries and U.K. gilts because of the unattractive returns from real yields.

"Old-fashioned gilts and Treasury bonds may need to be 'exorcised' from model portfolios and replaced with more attractive alternatives both from a risk and a reward standpoint," he wrote.

Gross cut the proportion of U.S. government and related securities in Pimco's Total Return Fund to 22% of assets in December from 30% in November, according to a report placed on the company's website on Jan. 14. He raised holdings of mortgage debt in December to 45%, the highest level since July 2009, from 43% as prices of government securities fell.

The real yield on 5-year Treasury Inflation Protected Securities was minus 0.35% today, down from the 5-year average of 1.29%.

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