variance-chartslisted

# Variance charts The core principle, and it is violated constantly: > **Plot the variance. Do not plot two lines and make the reader subtract.** Two overlaid lines show that a gap exists. A variance chart shows how big it is, which direction, and whether it is closing. The second is the question. --- ## Bullet chart — the default for actual vs target Compact, precise, and it replaces both the gauge and the two-bar comparison. ``` Revenue ▓▓▓▓▓▓▓▓▓▓▓▓▓▓░░░░ │ $4.82M / $5.10M plan (5.5%) under Gross margin ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓ │ 76% / 75% plan +1 pt Net burn ▓▓▓▓▓▓▓▓▓▓▓▓░░░░░░ │ $412K / $455K plan better └─ actual (bar) └─ target (tick) ``` - **Bar is the actual, a perpendicular tick is the target.** The tick reads as a threshold; a second bar reads as a second value. - Optional qualitative bands behind (poor / acceptable / good) — keep them very low contrast or they compete with the data. - **One row per measure, stacked**, sharing an axis where the units allow. Where they do not, give each row its own normalized scale and label the values. - Sort by variance magnitude, not alphabetically. Bullet charts fit a dozen measures in the space of one gauge and add the comparison. There is no case where a speedometer is the better choice. --- ## Deviation bars One bar per line item, drawn from a zero line, length = variance. Best when the question is *which items missed and by how much*. - **Zero line is