This wasn't just a bad year for the economy. By some measures, it was the worst year any American under age 70 has ever seen.

The loss of jobs in the US may be the biggest since the end of World War II. This year's declines in stock and home prices haven't been exceeded since the Great Depression. The slump in holiday spending may set a record; foreclosures already have. Credit markets seized, halting the longest expansion in consumer purchases.

For sale signs sit on the window of a former Circuit City store in New York.

Europe and Japan also sank as US demand faltered, marking the first simultaneous recessions since World War II ended. High-flying emerging economies, such as China and India, weren't immune, signaling the world economy is just as interconnected in bad times as in good.

"It was the year we wish it wasn't," said Harvard University professor Kenneth Rogoff, a former International Monetary Fund chief economist. "The global scale and magnitude" of the financial crisis and recession "is much greater than those we've seen before".

The National Bureau of Economic Research this month determined the US economy had been contracting for 12 months, already the longest downturn in a generation, with no end in sight.

The length and depth of the slump leave even the most experienced economists at a loss for superlatives.

"We've never seen this before and we don't really have a sense of where the bottom is going to be," Nobel laureate economist Edmund Phelps, 75, said.