Watch this key level in the bond market for signs of an inflationary shock to stocks, BlackRock chief Larry Fink says

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• BlackRock boss Larry Fink says there's a key level in the bond market for investors to keep tabs on.
• Once bond yields break 5%, it could signal an inflationary shock to the stock market, he said.
• Treasury yields have been volatile as investors consider the impact of Trump's latest policy moves.

Larry Fink is eyeing one number in the bond market: 5%.

That's the key threshold for the 10-year US Treasury yield that could...