Exchange-traded funds are all grown up...

The exchange-traded product (ETP) market has come a long way in the past 20 years. The SPDR ETF, the world’s largest exchange-traded fund (ETF), which tracks the S&P 500, had its twentieth anniversary in January, while the gold ETF, which includes the world’s second largest ETF, celebrates its tenth birthday this month.  Both ETFs highlight a trend that is symptomatic of any industry’s growth cycle: when new products are launched, the products with the largest potential for assets under management, as well as being the simplest to create and understand, come first. As the industry dev...