About 56% of all recommendations on S&P 500 firms are listed as buys, the most since 2002. It's one more data point that shows the extent of the euphoria sweeping markets after a blockbuster earnings season.

While analysts are historically a bullish bunch, they're turning even more optimistic in the face of relentless stock-market gains and corporate earnings that topped even the highest expectations. For all the concerns about the delta variant, China's regulatory crackdown or waning Federal Reserve stimulus, it hasn't made much of a dent yet on stock prices.

"It's not just financial conditions and low rates fueling the appetite for risk assets -- tremendous fundamental improvement is forecast into 2022," Todd Jablonski, chief investment officer at Principal Global Asset Allocation, said in a note.

U.S. companies aren't the only ones feeling the love. In Europe, about 52% of recommendations on Stoxx 600 firms are buy or equivalent, a 10-year high. In Asia, that number jumps to 75%, the highest proportion since at least 2010.

The second-quarter earnings season was one of the strongest in history, even if helped by comparison with a period last year when many parts of the world were in the grip of pandemic lockdowns. U.S. profit growth of 90% was 17 percentage points better than expected, while a 71% rise in Europe surprised positively by 16 percentage points, according to JPMorgan Chase & Co.