City Bus Fleet Forecast

A split-color bar chart uses one color for historical actuals and another for forecast years, creating an instant visual cue for where the data ends and the projection begins. Every bar uses the same height axis, so the trend reads continuously, but the color shift tells readers exactly when they cross from measured values into modeled ones. This is a small but important distinction in investor and analyst presentations, where conflating actuals with projections can undermine credibility.

This format is standard in automotive, transportation, and infrastructure decks. Fleet size projections, vehicle sales forecasts, energy demand outlooks, and population growth charts all use this structure. The chart is especially effective when the trend is steady and the projection simply extends it, because the continuity of the bars reinforces confidence in the forecast. When the trend inflects at the forecast boundary, the color split draws attention to that structural change.

Labeling each bar directly above it eliminates the need for a y-axis and grid lines, which reduces visual noise and makes the chart feel cleaner in a presentation context. The number of bars should stay between seven and twelve, enough to show a meaningful trend without making individual bars too narrow to read. When the trend inflects at the forecast boundary — accelerating or decelerating rather than simply extrapolating — annotate that year directly so readers understand whether the projection assumes a policy change, a demand shift, or a technology event rather than a modeling artifact.