11 billion

From Talking Points Memo:

Americans cut backon driving in March, compared to the previous March, more than in any single month since such record-keeping began in 1942. It was a 4.3 percent drop in miles driven, a reduction of:

11 billion miles.

("Day-amn!" say the staff at jer,uh...ME!)

[TPM continues]...I was doing a little more reading on this and came across this...from Time, circa 1947:

The average U.S. citizen completely ignores the regularity with which the automobile kills him, maims him, embroils him with the law and provides mobile shelter for rakes intent on seducing his daughters. He takes it into his garage as fondly as an Arab leading a prize mare into his tent. He woos it with Simoniz, Prestone, Ethyl and rich lubricants--and goes broke trading it in on something flashier an hour after he has made the last payment on the old one.

By last week, this peculiar state of mind had not only sucked thousands of American oil wells dry, stripped the rubber groves of Malaya, produced the world's most inhuman industry and its most recalcitrant labor union, but had filled U.S. streets with so many automobiles that it was almost impossible to drive one. In some big cities, vast traffic jams never really got untangled from dawn to midnight; the bray of horns, the stink of exhaust fumes, and the crunch of crumpling metal eddied up from them as insistently as the vaporous roar of Niagara.