Arthur J. Gallagher (NYSE:AJG) has outperformed the market over the past 20 years by 3.4% on an annualized basis producing an average annual return of 11.72%. Currently, Arthur J. Gallagher has a market capitalization of $64.32 billion. Buying $100 In AJG: If an investor had bought $100 of AJG stock 20 years ago, it would be worth $918.89 today based on a price of $293.58 for AJG at the time of writing. Arthur J. Gallagher’s Performance Over Last 20 YearsFinally — what’s the point of all this? The key insight to take from this article is to note how much of a difference compounded returns can…