"The parallels between our present situation and the period preceding the Great Depression are striking. Just as massive debt was accumulating in the market from the purchase of stocks 'on margin', so too, mortgage debt between 2000 and 2006 soared from $4.8 trillion to $9.5 trillion. In both cases the 'wealth effect' spawned a spending spree which looked like growth but was really the steady, insidious expansion of debt which generated economic activity."

See: Mike Whitney article (2007-02)