Here's the top reason US stocks aren't in bubble territory, according to Fundstrat's Tom Lee

• US stocks are not in bubble territory because 94% of retail inflows since 2008 have gone into bonds, not stocks, Fundstrat's Tom Lee highlighted in a note on Monday.
• Just $183 billion of retail money has flowed into the stock market since 2008, according to Lee.
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US stocks are set to perform "surprisingly well" over the next decade, in part because there is "no bubble in stocks," Fundstrat's Tom Lee said in a note on Monday.

Even after the S&P 500's 16% rally to record highs in 2020 during a global pandemic, investors are likely to see further gains in stocks because, since 2008, 94% of retail fund flows have gone into bonds, not stocks, Lee said.

Of the $3.1 trillion in retail fund inflows since 2008, just $183 billion, or 6%, went into the stock market. And in the past three years, fund flows into stocks have been weak, despite a nearly 70% surge in the S&P 500.

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"Investors liquidated stocks at an accelerating pace since 2017," Lee said. In the past few months, he added, there has been a "small blip" of flows into the stock market, but "how can this 'blip' mark the top??!!"

Since 2008, investors have poured $936 billion into bond exchange-traded funds, $1.9 trillion into bond mutual funds, and $2 trillion into stock ETFs while pulling $1.9 trillion out of stock mutual funds, the note said.

"Again, I don't see how this marks even the proximity of a top for equities," Lee said.