Younger, tech-savvy people are also more likely to play the digital currency markets and the high risk involved, Sunnarborg said. He estimates that about two-thirds of investors in cryptocurrencies are under age 40.

That same age category is less likely to invest in the stock market. Just one-third of millennials, or adults currently aged 21 to 35, said they owned a stock in a Bankrate study last July. In contrast, 51 percent of Gen Xers, or those age 36 to 51, said they owned a stock, and 48 percent of Baby Boomers, ages 52 to 70, according to the survey of 1,000 American adults conducted for Bankrate by Princeton Survey Research Associates International.

“The next generation is suffering from the same thing that the Gen-Xers suffered in the dotcom bust,” Winer said. “They’re playing all kind of markets that they know nothing about.”

He was referring to the speculative trading that ended in the stock market’s plunge in 2000.

Traders and market strategists also worry that a “fear of missing out trade” has helped send U.S. stocks deep into record territory — the S&P 500 has posted 24 record closes this year and is up 9 percent over that time.

The difference is this time, typical measures of overexuberance may not apply to stocks.

Bank of America Merrill Lynch’s June Global Fund Manager Survey found that while a record 44 percent of managers say stocks are overvalued, their cash holdings have actually have moved up to 5 percent, higher than the 10-year average of 4.5 percent. There’s “no irrational exuberance” in contrast with the 1999 bubble, the note said.

However, sluggish global growth and easy central bank policy could limit investment returns, while people remain wary about stock markets after the financial crisis.

“I do believe that in a market with few attractive alternatives, speculation tends to become rampant,” said Daniel Alpert, a founding managing partner at Westwood Capital. “And it almost doesn’t matter what people choose to speculate in, as long as they believe there is a fool greater than they out there somewhere.”

Facebook Comments