Average credit card debt:
http://www.usatoday.com/money/perfi/credit/2010-08-25-credit-card-balances_N.htm

If you combine that number with the average bank balance of $3800, perhaps that is the source of the number in the original post.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13