Group 1 - The U.S. stock market is expected to end May with strong returns, but this may negatively impact the market on Friday due to a projected $20 billion stock sell-off by U.S. pension funds as part of their month-end rebalancing operations [1] - The sell-off is attributed to many pension plans adjusting their stock-bond allocation ratios, necessitating significant adjustments to rebalance these asset classes [1] - The SPDR S&P 500 ETF Trust (SPY) has risen over 6% this month, while the iShares 20+ Year Treasury Bond ETF (TLT) has declined nearly 4% [1] Group 2 - Short-term bonds have performed slightly better, but even the Vanguard Short-Term Treasury ETF (VGSH) may record negative returns this month [2] - The volatility in the bond market is unusual, especially for pension funds or institutional investors with substantial assets [2] - HSBC has upgraded its rating on U.S. stocks from "underweight" to "neutral," partly due to lighter holdings by long-term investors [2] - Some investors may see the pension fund sell-off as a buying opportunity, especially if they believe recent trade issues will improve [2] - There is a general sentiment on Wall Street that the worst of the tariff issues may be over, with expectations of a calming situation [2]