While the economic policies of any Administration can and do affect the market and economy, most policies don't show results immediately. For instance, the tax-cuts and 'trickle-down' economics of the Reagan administration didn't bear fruit until four years after the Gipper left office - it can be argued that the boom of the 1990's was a direct result of the fiscal and economic policies of the 1980's.
BTW - Welcome to FR. :)