The second and perhaps more realistic explanation is that boomers don’t think their kids can handle all that money. Only 32 percent of baby boomers are confident their children will be prepared emotionally and financially to receive a financial legacy.

Granted, not all generations feel this way. Gen-Xers and Gen-Yers, along with the generation older than the baby boomers, are more disposed to leave money to their kids. More than two thirds of those aged 18 to 46 and those over 67 say it’s important to leave a financial inheritance to their children.

“Our survey points to a shift in generational behavior and outlook, most likely shaped by personal experience and societal responses to economic realities,” said Keith Banks, president of U.S. Trust. “The next generation has not experienced the consistently strong economic growth or investment returns that baby boomers experienced during the longest bull market in history.”

And there may be a third explanation: the baby boomers plan to spend most of their money. Given the low investment returns in today’s markets, their long lifespan and their famously non-apologetic lifestyles, the boomers are probably burning through their fortunes at a rate that won’t leave much for the next generation.

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