In 2010, gross sales margin as a percentage of new-car price was 4.4%; today it’s 2.5%. Relatedly, the largest US bank just reduced to zero the cost of stock and ETF trades for some of its customers, and a brokerage just introduced two stock index funds with no fees, hidden or otherwise, of any kind! Commissions appear to be increasingly under pressure the more competitive, commoditized and automated the industry.