Most presentations have some sort of written summary on the first page. You often almost skip it when presenting live, but it can be important for an important that reads your slide deck at the computer rather than attending a live presentation.

The one thing that I find really hard to summarise are financials. Prose that goes like "sales were x, up y% compared to last quarter but z% versus the same quarter last year at a slightly higher operating margin of v%" makes me totally lose the picture.

Financial journalists fill pages of the Wall Street Journal with this type of texts. And they are upset that it is now possible for an automated bot to do this job: insert a financial table and out comes a perfectly written paragraph. (Robo journalism)

What do I do as a reader? I reconstruct the table back in my head. 

So what to do in a presentation? I recommend a super simple written summary on page 1 (sales were up, but profits down), and then a very crisp financial summary table on the next page. Round up numbers, and use colour coding to show what went up or down.

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