The second-half setup for stocks: Don't fight the tape but keep expectations in check

Traders on the floor of the New York Stock Exchange, June 25, 2021.
Source: NYSE

Through nearly half the year, 2021 has delivered investors about three times more reward than risk, the S&P 500's 14% return coming with a few brief declines of no more than 5%.

In markets as in sports, momentum and mean-reversion are always either in force or in reserve, and a win streak reliably spurs a debate over whether a team has built unbeatable chemistry or is "due" for a rough patch.

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