Big Wall Street investment companies are pulling back slightly on their borrowing from the Federal Reserve's emergency lending program.

A central bank report Thursday said they averaged $32.6 billion in daily borrowing over the past week. That compares with $38.1 billion in the previous week and $32.9 billion before that.

T.J. Marta, a fixed-income strategist at RBC Capital Markets, viewed the pullback as a positive sign. "Conditions in this particular part of the financial markets are easing up somewhat," he said.

The program, which began March 17, is part of the Fed's effort to aid the troubled financial system, whose problems threaten the nation's economic health. In the program's first week, investment firms borrowed $13.4 billion.

The Fed has agreed, for the first time, to let big investment houses temporarily get emergency loans right from the central bank. This mechanism, similar to one available for commercial banks for years, will continue for at least six months. It was the broadest use of the Fed's lending authority since the 1930s.

Fed Chairman Ben Bernanke and his colleagues started the program as policymakers raced to deal with the sudden crash of the venerable Wall Street firm Bear Stearns Cos., which was on the brink of bankruptcy.

The Fed feared that other investment houses could be in jeopardy given the intense fear that gripped the markets at that time. So the Fed acted to give them a place to go for overnight cash loans.

The program is seen as similar to one the Fed has for commercial banks, where the Fed acts as a lender of last resort. Commercial banks and investment companies pay 2.5 percent in interest for overnight loans from the Fed.

Banks averaged $10.2 billion borrowing for the week ending April 9. That compares with $7 billion for the previous week. The identities of commercial banks and investment houses are not released.

Also Thursday, the Fed auctioned an additional $33.95 billion in super-safe Treasury securities to big investment firms. That was less than the $50 billion worth of securities the central bank had made available.

The results of the auction — the third of its kind — suggest that demand for the Treasury securities may be easing. That might be viewed as a sign of improvement in credit conditions, some analysts said. Demand for Treasury securities, backed by the government, had shot up in recent months as financial market turmoil intensified and investors flocked to safety.

The auction "is a positive sign that they (investment firms) are not gobbling up every Treasury security in sight. It's a good sign there is little less stress in the financial system," said Phil Flynn, senior market analyst at Alaron Trading Corp.

In exchange for the 28-day loan of Treasury securities, bidders can put up more risky investments as collateral, including certain mortgage-backed securities.

In the three auctions so far, the Fed has provided $133.95 billion worth of Treasury securities.

The program is intended to help financial institutions and the troubled mortgage market. The Fed said it would make as much as $200 billion worth of Treasuries available through weekly auctions.

The goal is to make investment houses more inclined to lend to each other. It also is aimed at providing relief to the distressed market for mortgage-linked securities. Questions about their value and dumping of these securities have driven up mortgage rates, aggravating the housing crisis.