Index-to-baseline

Pick one reference point, call it 100, and restate every other value as a percentage of it. Unlike a fairer denominator, this fixes a common starting line, so series in different units can share one chart and be read against each other.

Pick one reference point, call it 100, and restate every other value as a percentage of it. Unlike a fairer denominator, this fixes a common starting line, so series in different units can share one chart and be read against each other.

Example

Set week one to 100 for both series: weight 212 pounds and 8,400 daily steps. Six months later weight sits at 94 and steps at 137. On one chart you see the seven percent drop and the 37 percent activity gain moving together.