LOS ANGELES — Crammed inside a big metal box, Charlie Woo's toys make their way from Asia to his downtown Los Angeles warehouse. Lately, the trip has become less expensive for containers of miniature tea sets, remote-control cars and super-size squirt guns.

Woo, owner of Megatoys, says a drop in shipping rates is saving him $50 to $100 for each cargo container he fills. That might not sound like much, but Woo uses 2,000 of the 40-foot containers a year, so that amounts to at least $100,000 in annual savings, he said.

Woo is benefiting from a slowdown in the furious growth pace of international trade, combined with a building spree of ever-larger ships.

"If their ships are full and their business expands, they want to raise the rates," Woo said. "I think the ships are not completely full, and the competition to fill them is fierce."

The shipping industry had enjoyed five years of rising freight rates. Now, the world's largest shipping line is warning of lower earnings, and maritime experts say economic head winds could bring even more of a cool-down.

"The deluge hasn't hit yet, but we will see more and more vacant space on these ships," said Mark Page, of Drewry Shipping Consultants of London.

In 2003 and 2004, worldwide trade grew by 14 percent. The growth rate slowed to 11.5 percent in 2005 and is expected to drop to less than 10 percent in 2006 and about 9 percent in 2007, Page said.

Piers Global Intelligence Solutions, a private data service that tracks imports and exports based on shipping documents, has predicted U.S. import growth of 9 percent this year and 7 percent in 2007 and U.S. export growth of 10 percent in 2006 and 9 percent in 2007.

In Los Angeles and neighboring Long Beach, the busiest U.S. container port complex, there is no hint of a slowdown. The ports are predicted to handle the equivalent of 15.6 million 20-foot containers in 2006, an increase of nearly 11 percent from last year's record pace, which was up 8 percent from the year before. Twenty-foot containers are the standard gauge for containers of varying size.

But several factors are weighing on the industry.

Chief among them is the growing evidence of economic cooling in the U.S. and other countries, coupled with rising prices and interest rates. Signs of inflation, particularly red-hot energy costs, led Federal Reserve Chairman Ben S. Bernanke on Monday to pronounce the price trends "unwelcome" and the U.S. economy "in a period of transition."

With more money going to gasoline and other basics, less cash might be available for other things, including the imported products that arrive by the shipload each day.

"Consumers will have less spendable income," said Guy Fox, a Yorba Linda, Calif., shipping consultant. "They might take the SUV on a family vacation, but they won't buy the new high-definition television. People will put up with what they have, and that will have a domino effect on the whole economy."

Another factor that could slow shipping growth is that many U.S. and European manufacturers already have moved their manufacturing overseas, bringing a moderating in new outsourcing, said Page.

At the same time, container ship capacity is predicted to grow 14 percent this year and 11 percent in 2007, Page said.

"For some time now, we have been receiving far too much in the way of ships and in very large ships in particular. Now, we are looking at three years to 3 1/2 years of overcapacity," Page said.

The world's largest shipping company is feeling the pinch.

In March, Copenhagen-based A.P. Moller-Maersk warned that earnings would fall "considerably" because of a sharp decline in rates. That sparked a round of stock downgrades by investment companies.

However, those assumptions aren't shared by the Transpacific Stabilization Agreement, a group of 11 major container shipping lines that carry more than 70 percent of the boxed cargo that moves between Asia and the U.S. Its executive director, Albert A. Pierce, said that trade growth might slow, carriers expect a gradual slowing of cargo growth, not a steep drop.

Niels Erich, a spokesman for the shipping group, added that in the past many U.S. manufacturers relied on China.

"There has been a shift in the trans-Pacific market," he said. "China ... is a supplier to the U.S. now."