The Federal Reserve's profit is dropping, but it's nothing to get worried about, says Allan Sloan, senior editor at large for Fortune.

The Fed has been "a cash cow for U.S. taxpayers ever since the worldwide financial bailout began five years ago," because it sends its investment profits to the Treasury Department, he writes.

Using numbers from Stone McCarthy Research Associates, Sloan estimates the Fed has forked over $366 billion to the Treasury "and thus U.S. taxpayers" during the past five years. That compares with the $150 billion or so the Fed probably would have delivered if it hadn't bought huge quantities of bonds to keep interest rates down, he explains.

Editor’s Note: 18.79% Annual Returns . . . for Life?

But while the Fed's security holdings increased by about $1.1 trillion last year, the amount of money that the Fed sent to the Treasury decreased to $76.5 billion from $88.4 billion in 2012, according to Stone McCarthy.

The 2013 decline merely stems from one-time profits the Fed earned selling assets in 2012, Sloan says. Without the one-time sales, the Fed's profit would have risen 10 percent last year, according to Stone McCarthy's numbers.

"If Fed remittances stop for a year or two, we shouldn't get too upset with old Bossy and try to put her out to pasture," Sloan quips. "We should remember that taxpayers got to skim the cream off the Fed's securities portfolio when the Treasury really needed the money."

The Fed's balance sheet has now surpassed $4 trillion, but that heft won't prevent the central bank from administering monetary policy effectively, says Richmond Fed President Jeffrey Lacker.

The interest it pays on excess bank reserves deposited at the Fed helps give it control over short-term interest rates, he said in answering questions after a recent speech, Reuters reports.

Editor’s Note: 18.79% Annual Returns . . . for Life?

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