When revenue misses plan by eight percent, the first instinct is often a bar chart: planned versus actual, red and green. Directors see the gap. They do not always see why the gap opened where it did.
Bridge before bar
For board variance slides we default to a waterfall or bridge chart when more than two drivers explain the miss — FX, volume, price mix, one-off charges. The bar chart stays in the appendix for auditors who want the simple comparison.
When a slope chart wins
If the conversation is trend rather than variance — twelve months of margin rate, for example — a slope or small-multiple line chart reads faster than quarterly bars. We label the last point prominently because that is where the chair's finger lands.
The question we ask before picking
"What decision does this slide support?" If the answer is approve the forecast revision, show drivers. If the answer is note compliance with covenant, show the single metric and threshold line. Chart type follows the decision, not the spreadsheet layout.