But you can inspect its past. They use these to make projections into the future. If the share acts true to form, and you put your money on it, you're in clover. Trouble is history isn't supposed to repeat itself and just less than a third of my phalanx of expert informants think chartism is for the birds. The rest of them agree you can't predict the future by looking at the past - except, that is, in the peculiar world of shares.
Past performance can be the key, they claim, to share price in the future.
And the consensus view seems to be that while charts shouldn't be used as sure indicators on their own, it's all right to lump their results with other buy or sell signals. You might imagine chartists simply draw straight lines to show whether a share is heading north or south, rather like those simple graphs you find on office walls, in business cartoons. But they've turned it into a more c9mplicated process than that. Chartists draw the basic line showing the shares progress, then they intersect it with other lines, curves and squiggles. The resulting diagrams don't tell an obvious story, and you need the skills and knowledge of a tea-leaf reader to make sense of them.