Investment Performance - An investment of $10,000 in the S&P 500 index at the beginning of 2005 would grow to $71,750 by the end of 2024, yielding an annual return of 10.4% [1] - Missing the best 60 days in the market from 2005 to 2025 would reduce the investment value to $4,712, resulting in a return of -3.7% [2] Trading Insights - Mondays are historically the weakest day for markets, often referred to as the "Monday Effect," where stocks tend to open lower [4][5] - Factors such as weekend news and investor sentiment contribute to downward pressure on the market at the start of the week [5][7] - Short-term traders should avoid selling on Mondays to prevent losses and consider buying stocks on this day to take advantage of lower prices [8] Optimal Trading Days - Tuesdays through Thursdays have shown stronger performance for trading, with Fridays often experiencing a bump as traders position themselves ahead of the weekend [9]