Home Depot was a tiny startup with just four stores at the time of its successful 1983 IPO. Forty years later, thanks to the billions of dollars of regulatory costs and hurdles from laws like Sarbanes-Oxley and Dodd-Frank, few start-up companies can afford to go public.

This chart from Apollo Wealth Management shows the decline in publicly traded companies, which means less access to capital and fewer opportunities for mom-and-pop investors to get in on the ground floor of the next big thing.

Our friend, Norm Champ, who served as an SEC commissioner (and should be the next SEC chairman), notes that one reason to be concerned about fewer IPOs is that there is a shortage of public traded companies for retirement plans to invest in. So all the investment money gets crowded into the 25 or so largest corporations – which leads to a further concentration of wealth.

It’s all explained in Champ’s book, Going Public.