Group 1 - Moody's downgraded the U.S. credit rating due to rising government debt and increasing interest expenses, which may lead to higher borrowing costs across the economy [3] - The 10-year Treasury yield rose above 4.5%, impacting mortgage rates and borrowing costs for businesses and consumers, with the yield closing at 4.48% on Tuesday [3][4] - Higher yields are expected to pressure stock valuations, as they indicate increased borrowing costs for companies and intensify competition from fixed-income investments [4] Group 2 - Historical data shows that when the 10-year Treasury yield exceeds 4.5%, the stock market often faces pressure, as seen at the end of 2023 when the S&P 500 dropped significantly [4] - Morgan Stanley's strategist noted that the 4.5% threshold for the 10-year Treasury yield has been a critical point for stock market valuations, suggesting potential for moderate valuation compression if this level is breached [4] - Despite potential valuation pressures, there may be buying opportunities, especially in light of recent positive developments in U.S.-China trade relations [4]