But, looking at the data through 1996, the surging stock market does not seem to have imparted as big a boost to spending as past relationships would have predicted. The lack of a more substantial wealth effect is especially surprising because we have also seen a noticeable widening in the ownership of stocks over the past several years.
Relationships in practice can be different from what they are in principle, so the independence of the central bank depends on the evolution of informal as well as formal relationships between the central bank and the rest of government.