Washington ? Feeling the pinch from the Federal Reserve’s yearlong campaign to raise interest rates? Chances are you have a home equity line of credit or owe money on your credit cards.

But for other borrowers, it’s been a mixed bag. Rates for 30-year mortgages, for example, have gone down.

For savers, rates on a one-year certificate of deposit have risen during the past year, but rates on five-year CDs have barely budged.

“It’s a mixed picture. Short-term rates have climbed from extremely low levels, while long-term rates are at or near historic lows,” said Lynn Reaser, chief economist at Banc of America Capital Management. “This discrepancy in rates has affected borrowers and savers.”

A puzzled Fed Chairman Alan Greenspan has called the divergence of short-term rates and long-term rates a “conundrum.”

Greenspan and his Fed colleagues are poised to raise their key short-term interest rate, the federal funds rate, by one-quarter of a percentage point to 3.25 percent when they wrap up a two-day meeting Thursday.

That would be the ninth such increase since June 2004, when the Fed began to tighten credit.

In response, commercial banks are expected to boost their prime lending rates by a corresponding amount to 6.25 percent, which would be the highest since the summer of 2001.

Before the Fed embarked on its rate-raising campaign, the prime rate, used for many short-term consumer loans, stood at 4 percent, the lowest level since 1958; the federal funds rate, the interest banks charge each other on overnight loans, was at 1 percent, a 46-year low.

Extraordinarily low rates had once been needed to rescue the economy from the 2001 recession, the terror attacks and a wave of corporate scandals that had rocked Wall Street. But the Fed during the last year has been gradually reining in the easy credit, an approach aimed at preventing inflation from becoming a problem while keeping the economy growing.