Top Wall Street strategist explains why he's abandoning an S&P 500 target

- Piper Sandler will no longer release year-end price targets for the S&P 500 ($^GSPC) - The firm found that a small group of high-performing stocks significantly influence the market's activity - The top 10 stocks represented 75% of the index’s year-to-date returns - Nvidia ($NVDA) was solely responsible for nearly one-third of the S&P 500’s gains as of late June - Piper Sandler recommends prioritizing "quality at a reasonable price" in investing - Multiple strategists raised their targets for the S&P 500 this year due to the record-breaking rally - Year to date, the S&P 500 is up nearly 17%