Recent data shows that 78 S&P 500 companies have issued negative EPS guidance for Q1 2024, higher than the 5-year and 10-year averages. Analysts have reduced Q1 EPS estimates by 2.3%, below the averages. S&P 500 is expected to report lower Y/Y earnings and revenue growth for Q1 2024 compared to previous estimates. The trailing and forward 12-month P/E ratios for S&P 500 are above their respective 5-year and 10-year averages. Buybacks by S&P 500 companies increased in Q4 '23 but declined for 2023, impacting EPS negatively for the fifth consecutive quarter. Apple bought back $429.5 billion worth of its stock between 2019-2023.