We appear to have reached the danger zone in terms of Net Worth to Disposable Income:

Historically, this has not boded well for the economy or asset prices and can really only be sustained with cheaper and cheaper capital (debt at a zero rate or equity foolishly provided).  We know Central Banks are the providers of the mispriced capital.  That analysis is easy.  However, unlike in past bubbles where the capital was significantly from private sources that were ultimately subject to market discipline, the CBs have unusual ability to provide mispriced capital indefinitely (QE becoming debt cancellation).  This is why the ratio has already managed to stay afloat at current levels for almost three years and why it is very hard to determine whether the extension of this picture is a crash (of asset values) or just a decade long flat line of asset values as incomes slowly creep up.  Neither is a vigorous economic scenario, but the latter would be more pleasant for most than the former.