Dataskera

Variance Chart

Actual against plan on one line per account, with the deviation drawn in its own panel measured from zero. The actual is the bar, so how far it reaches still means the amount; the plan crosses that bar as a needle rather than standing beside it as a second bar competing for length. A gap is a quantity in its own right, so it gets a panel of its own, in the amount and in percent, with a second pair for the previous year when a third measure is mapped.

Data Requirements

Your Tableau worksheet should include:

  • 1 Dimension for the Category encoding. One line per value: an account, a cost centre, a product, a month.
  • 1 Measure for the Actual encoding. What happened. It is the length of the bar.
  • 1 Measure for the Plan encoding. What it is compared against: budget, target, forecast. It crosses the bar.
  • 1 Measure for the Previous encoding. Optional: a second comparison, usually the same period last year.

Add Variance Chart to your worksheet

First, download the manifest file. It tells Tableau where to load the extension from.

Download variancechart.trex

Direct link: https://dataskera.com/downloads/variancechart.trex

Then, in Tableau:

  1. On the Marks card, open the Mark type dropdown, and under Viz Extensions choose Add Extension.
  2. In the Add an Extension dialog, choose Access Local Viz Extensions, then open the variancechart.trex file you just downloaded.
  3. When Tableau asks, allow the extension to access the data in the workbook.
  4. The welcome screen appears. Sign in with your Dataskera account, or on Tableau Desktop choose Use on Desktop without an account. See Signing in & access below.
  5. Build the chart: drag a dimension onto Category, the measure that happened onto Actual, and the one it is measured against onto Plan. Add a third measure to Previous for a second comparison.
Tableau Server or Cloud:
A site admin must allow the extension by adding its URL to the site's safe list, and the view needs the Download Summary Data permission. Extension URL: https://vizextension.dataskera.com/variancechart/variancechart.html

Signing in & access

Variance Chart is free. Whether you need to sign in depends only on what you are doing. Viewing a dashboard never asks for an account, and authoring is free too.

Viewing a dashboard
No account

People who only view a dashboard are never asked to sign in and are never blocked.

Editing on Tableau Desktop
Optional

Sign in, or continue without an account in a single click.

Editing on Server or Cloud
Free account

Sign in with your Dataskera account to author on the web.

No account yet? Create one free in under a minute. No credit card required.

Format panel

Open the Format panel from the extension menu to customize the chart. It is for the dashboard author and is not shown to viewers. It has four tabs:

  • Reading the Deviation: which direction is good, whether the deviation panels show the amount, the percent or both, the sort, and the total line.
  • Deviation Colors: the favourable and unfavourable colours, which carry meaning rather than decoration and so sit here rather than in the palette.
  • Bars: bar thickness, row gap, the plan needle, and the panel headings.
  • Labels: the actual at the end of its bar and the deviation next to its own.
  • Color: a palette, a precise colour per category, and the overall opacity.
  • Legend: show or hide it, its position around the chart, an optional show/hide toggle for viewers, the colour swatch, and the content of each entry.
  • Tooltip: show or hide it, its colours, decimals, and a template you write yourself from the placeholders the chart provides.
Say once which direction is good:
On revenue, above plan is good. On cost, above plan is a problem. Nothing in the data carries that, so the author declares it and every colour follows. Choose lower is better and the chart says so in its data notes, rather than leaving a reader to work out why an overrun is red.
A plan of zero has no percentage:
Those rows read n/a and are counted in a note. A percentage against zero does not exist, and printing an infinity or a blank would be worse than saying so.
A negative plan keeps its direction:
The percentage is measured against the size of the plan, so minus sixty against a plan of minus a hundred reads as forty better, which is what happened. A raw ratio would flip the sign for a reason that has nothing to do with performance.
A percentage against a small base is clipped, not hidden:
Forty against a base of ten is three hundred percent, and on a shared scale that one row flattens every other bar. The percentage panels clip at four times the typical size, the off-scale bar is cut at the edge, and its real number is always printed. Amounts are never clipped, because an amount is the magnitude itself.
The total divides the sums:
Sum of the actuals over sum of the plans. It never averages the row percentages, which answers a different question. The total is also left off every scale and drawn cut, because being the sum of every row it would otherwise shrink all of them to slivers.
Panels drop when the pane is too narrow:
The percentage panels go first, then the second comparison, and the chart says what it left out and that widening the pane brings it back.