David Bowie, who turned 66 this week and is releasing his first album in ten years, in the unlikely hit “Changes” sang about having to be a different man.

The same can be said about stock brokers who as a group are facing a tectonic shift in their industry as ETFs continue to rise in popularity and allow investors to buy whole slices of the market with one online trade. Some discount brokers even let customers trade ETFs for free. [Schwab Mulls Commission-Free ETF Platform]

“Some stock brokers are likely feeling quite queasy as they regard their near and long-term futures. Will they become extinct in the next 10 to 20 years?” Jake Zamansky writes for Forbes. “Retail investors are fleeing in droves from stock and bond mutual funds pushed by their stock brokers and piling into ETFs … which offer the same investments.”

The underperformance of active fund managers has also played a part in driving disgruntled investors to index-based ETFs. [You’re Fired: Investors Drop Underperforming Fund Jockeys and Buy ETFs]