The Globe and Mail reports in its Saturday edition that every new year, investing's greatest visionaries on Wall Street predict where the stock market will be at the end of the year. The Globe's Tim Shufelt writes that the predictions for how the S&P 500 index would perform in 2024 ranged from a loss of 12 per cent to a gain of 15 per cent. The index ended the year up by 23 per cent. It was a similar story in 2023. The rosiest prediction going into the year called for an increase of 17 per cent in U.S. stocks. The S&P 500 ended the year on a 24-per-cent gain. Granted, those were two extraordinary years, but the practice of stock-market prognostication is just as inept over longer time frames. Vanguard Group looked at the reliability of market forecasts since the end of 2010. The analysis found that 75 per cent of the time one-year returns were either higher than the most optimistic forecast, or lower than the most pessimistic. A 9-per-cent long-term average return almost never materializes in a single year. Meaningless and futile are the most charitable descriptions for such forecasts. Nine per cent a year appears to be a durable result over long horizons. The Canadian stock market is much the same.