Compare mode

Compare mode shows a visual's two sides next to each other, with their difference. Turn it on for one visual, name the sides, and read the change as extra columns, a series or a split layout; you can also scope a slicer so it filters only one side. How the compared outputs are built, and the hint shown when the two sides never meet, are on Compare mode.

Turn on Compare

1. Select Edit in the report header. It appears only when you can edit the report; for saving, see Build a report.
2. Select one visual that supports compare (the list is below), and open its Visual tab.
3. Find the Comparison section and switch Compare on in its header. The section appears only for visual types that support compare.
4. Under Show, each output has its own switch: the two sides, Diff and Diff %. The two sides and Diff start on; switch Diff % on to add the percentage.

While Compare is off, the section hints what it will show, using your side names: Turn on to show First and Second side by side, with their difference.

The other sections of the Visual tab are covered on Format a visual.

Which visuals can compare

• Compare uses exactly two sides; the rule in full is on Compare mode.
• In a Table or Matrix, Compare adds a column for each side, plus Diff and, when switched on, Diff %.
• The full catalogue of visual types is on Visuals.

Name the sides and the difference

• The sides start out named First and Second.
• Diff label and Diff % label rename the difference and its percentage on the visual and in a download. Leave either field blank and its default name (Diff or Diff %) comes back.
• On a slicer scoped to one side, the Scope label names that side; the field's explanation reads Shared by every slicer on this side and by the compare tiles.
• Label length follows the naming rule on Compare mode.
• Each difference label can carry an icon. The picker's control reads Add an icon to Diff or Diff icon; the search field reads Search icons, and Remove icon clears it. When nothing matches your search, the picker reads No icon matches that name. The icon then shows beside the label in Table and Matrix headers and in tooltips.

Read the numbers

• Diff is the first side minus the second side. Where only one side has a value, the other side stays empty.
• Diff % is calculated for numeric values only, including counts such as Count and Distinct; counts stay whole numbers. It prints as a percentage with one decimal place, and stays empty when the second side is zero, because the share is undefined then.
• A date value gets its difference in days, and a date and time value in seconds, instead: these show a Diff but never a Diff %.
• A text value shows both sides without a difference.
• When the two sides do not overlap on the axis at all, every row is one-sided; the visual shows the overlap hint, quoted on Compare mode. Pick fields both sides share, or turn Compare off.

Legends and Compare

• A legend field and Compare compete for the same slot.
• While Compare is off and a field sits in Legend, the switch is disabled and its tooltip reads Remove the Legend field to compare: a legend and two scopes would multiply the series.
• While Compare is on, adding a legend field pauses it: Compare is paused while a Legend field is set: the two scopes take the legend slot. Remove the Legend field to compare, or turn Compare off. Remove the field from Legend to resume.

Split the visual or plot the difference

• On Bar, Combo and Line, a toggle in the Comparison section plots the difference as its own series beside the two sides. The toggle carries your diff name, for example Plot Change as a series.
• On Pie, Donut and Funnel, Split chooses how the sides share the visual: Auto, Side by side or Stacked.

Scope a slicer to one side

• Comparison scope appears on a slicer, and on a custom visual that acts as a slicer.
• Set Scope to Both, the first name or the second name. Picking a side makes the slicer filter only that side; until you pick one, the hint reads Pick a side to make this slicer filter only First or only Second. (your side names stand in for First and Second).
• The Scope label names that side for every slicer scoped to it and for the compare tiles. Clearing the field while you type does not snap it back to the old name.
• On a slicer group, setting the scope reaches every member of the group.

Exports and downloads

• A download of a compared visual renames its columns using your compare labels, so the file reads as the sides and the difference.
• If two of your labels would produce the same download header, the download is refused until you change the compare labels.
• Downloads in general are covered on Export reports and data.

Questions, answered

Which visuals can I compare?

Compare works on Bar, Combo, Line, Pie, Donut, Funnel, Key tree, Table, Matrix and KPI visuals. Plotting the difference as its own series is offered on Bar, Combo and Line, and the Split layout on Pie, Donut and Funnel.

Why is the Compare switch disabled?

A field sits in the Legend well, and a legend plus two sides would multiply the series. The tooltip reads Remove the Legend field to compare: a legend and two scopes would multiply the series. Remove that field and the switch frees up.

Why did Compare pause after I added a Legend field?

With Compare already on, a legend field pauses it instead of disabling it: the two sides take the legend slot. The section reads Compare is paused while a Legend field is set: the two scopes take the legend slot. Remove the Legend field to compare, or turn Compare off. Remove the field from Legend to resume, or turn Compare off.

Why does one side of my comparison show no values?

A value that appears on only one side has nothing to show on the other, so that cell stays empty. When the two sides do not overlap on the axis at all, every row is one-sided, and the visual shows the overlap hint, quoted on Compare mode. Pick fields both sides share, or turn Compare off.

What does the Diff column show?

The first side minus the second side. It stays empty where only one side has data.

Why is there no Diff % on my date or text column?

Diff % is only calculated for numeric values, including counts. A date value shows its difference in days, a date and time value in seconds, and a text value shows the two sides only.

What does Diff % show when the second side is zero?

Nothing: the share is undefined when the second side is zero, so the cell stays empty. The absolute Diff still shows.

Can I plot the difference as its own series?

Yes, on Bar, Combo and Line. Turn on the series toggle in the Comparison section; its label carries your diff name, for example Plot Change as a series.

How do I split a pie into two halves?

Use Split in the Comparison section and choose Auto, Side by side or Stacked. The option is offered on Pie, Donut and Funnel only.

How do I make a slicer filter only one side?

Open the slicer's Comparison scope and set Scope to the side you want, or to Both. The Scope label names that side for every slicer scoped to it and for the compare tiles. On a slicer group, the scope reaches every member.

Do the compare labels change the numbers?

No. The labels only name the outputs on the visual and in a download; they never enter the query, so the numbers are the same whatever you call the sides.

Why is my download of a compared visual refused?

Two of your labels would produce the same download header, and a file cannot carry two identical columns. Give the sides and the difference distinct names, then download again.