The average S&P 500 forecast hasn't been this much lower than the actual market since 1999

• The average year-end forecast for the S&P 500 is 2,933, according to Bloomberg data.
• On Monday, the index closed at 3,232.39, erasing year-to-date losses.
• The gap between strategists' year-end expectations and the market's actual performance is the widest since 1999, Bloomberg reported.
• Read more on Business Insider.

The gap between S&P 500 forecasts and the actual market hasn't been so wide since 1999, Bloomberg reported Monday.

The average forecast for the S&P 500 year-end level is 2,933, according to Bloomberg data. But on Monday, the index soared to a close of 3,232.39, rising more than 1% to erase its year-to-date losses.

The gap between the forecasts and the market's actual performance is now at the widest since 1999, Bloomberg data show.

Many strategists and famed billionaire investors including Stanley Druckenmiller have been cautious of the market's searing rally from March 23 lows hit amid the coronavirus pandemic. But that didn't stop the index from rallying 44% from its March low, fueled by investor hopes of a swift economic recovery.

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Even before the index surged Monday, it was trading above the average year-end target. On Friday, the S&P 500 closed at 3,193,93, which was higher than all but four year-end targets based on a survey of 18 Wall Street forecasters, according to Bloomberg.

The lowest year-end target for the index is 2,500, held by Maneesh Deshpande at Barclays, according to Bloomberg. It represents a nearly 23% slump from Monday's close.

Some strategists think that the S&P 500 is currently trading too high. And, while it's erased year-to-date losses, the index is still trading about 4.7% below the all-time high hit on February 19.

On Monday, Bank of America issued a "mea culpa" and boosted its S&P 500 target to 2,900 from 2,600. Still, strategists led by Savita Subramanian, the bank's head of US equity and quantitative strategy, wrote that the index was trading above fair value.