Mimicking President-elect Donald Trump - who has called himself "the king of debt" - risk-loving millennials invested heavily in ETFs that employed leverage to juice their returns in the wake of the real-estate mogul's election victory. With a preference for gold and volatility, they were largely in line with what the consensus called for in the event of a Trump victory -  in other words, far off the mark, and that didn't work out so well for them.

"From triple X leveraged products to Vanguard, Millennials have shown they favor the extremes in terms of their growing ETF usage," said Bloomberg Intelligence ETF Analyst Eric Balchunas. "However, when it comes to calling the Trump rally, they weren't alone in getting it wrong - every generation thought gold would rally."

The investments of choice were:  a pair of triple-levered ETFs that own gold miners (NUGT and JNUG); ProShares Ultra VIX Short-Term Futures, which tends to benefit from increases in stock market volatility; iShares Russell 2000 ETF; Vanguard Total Stock Market ETF. 

Positive & Negative Take Aways.    By favoring low-cost Vanguard funds, Millennials exhibited a long-time horizon and a decent risk appetite. But by trying to time the market with tactical trades, and by favoring triple-levered oil ETFs and other products that have up to 14 times the volatility of the S&P 500 index, they turned themselves into adrenaline junkies.