There are two reasons for this: first, the important contribution of US consumer spending to global economic activity; and, second, the continuing high exposure of global financial institutions to securities backed by US mortgages and consumer loans. According to the IMF, these exposures amount to USD 1.3 trillion.
Since the end of 2008, private consumption in the US has recovered somewhat after a significant decline in the second part of 2008. This decline resulted from weak income growth, rising unemployment and a rapid deterioration in the balance sheets of US households. Total net household wealth in the US declined by USD 7.8 trillion (or 13%) in the second half of 2008.