The relentless slide in home prices has left nearly one in six U.S. homeowners owing more on a mortgage than the home is worth, raising the possibility of a rise in defaults -- the very misfortune that touched off the credit crisis last year.

The result of homeowners being "under water" is more pressure on an economy that is already in a downturn. No longer having equity in their homes makes people feel less rich and thus less inclined to shop at the mall.

And...