Keep in mind that this is an 'average' and that exogenous events can greatly affect the normalized results.
Chart courtesy of friend Brian at ContraryInvestor. 
Gold Seasonality with Gold 2010 Daily Price Chart Overlay
“Modern tyranny is terror management. When the terrorist attack comes, remember that authoritarians exploit such events in order to consolidate power. The sudden disaster that requires the end of checks and balances, the dissolution of opposition parties, the suspension of freedom of expression, the right to a fair trial, and so on, is the oldest trick in the Hitlerian book. Do not fall for it.”
Timothy Snyder, On Tyranny
Keep in mind that this is an 'average' and that exogenous events can greatly affect the normalized results.
Chart courtesy of friend Brian at ContraryInvestor. 
Gold Seasonality with Gold 2010 Daily Price Chart Overlay