Period over period comparison in time series visualizations

concept australia Updated Oct 2, 2026 3 min read period-over-period-comparison.md
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Period over period comparison overlays several time periods of an indicator on one time series visualization so that you can spot patterns, trends, and anomalies across the periods.

When you turn on Compare period over period in the Date range settings of a time series visualization, each period appears as a separate series on the same chart. The periods are aligned by their position within the period, so you can compare, for example, each year's January or each quarter's first month. Without period over period comparison, the visualization shows a single timeline.

Note: Period over period comparison is available starting with the Brazil release.

Requirements

The Compare period over period setting is available only when the visualization meets all of the following conditions:

  • The data source is an indicator. Table data sources aren't supported.
  • The visualization is a time series with a single metric and no group by.
  • The Number of periods and Period settings are configured.
  • The chart type is Area, Line, Spline, or Step. Column and Scatter charts aren't supported.
  • The visualization doesn't use Show maximum range or Set absolute period.

Dashboard filters don't work with a time series that has period over period comparison turned on.

When the setting is hidden

The Compare period over period setting is hidden, not turned off, in these cases. The visualization then shows a single timeline, and no message appears.

  • The Period is Days.
  • The time aggregation unit is the same as the Period unit. For example, the time aggregation is By month and the Period is Months.
  • The indicator source or the indicator definition uses a business calendar. Standard and Gregorian calendars aren't business calendars.
  • The indicator is a Data snapshots indicator with a business calendar defined in its trend settings.

If you add a business calendar to the indicator source or definition, the visualization reverts to a single timeline on the next display.

Period units and time aggregation

The Period options are Days, Weeks, Months, Quarters, and Years. The options depend on the time aggregation. A period can't be shorter than the time aggregation unit.

Time aggregation Available periods
Daily Days, Weeks, Months, Quarters, Years
By week (SUM, AVG, or LAST) Weeks, Months, Quarters, Years
By month (SUM, AVG, or LAST) Months, Quarters, Years
By quarter (SUM, AVG, or LAST) Quarters, Years
By year (SUM, AVG, or LAST) Years

If you change the time aggregation to a unit longer than the current Period, the Period changes automatically to the shortest period that is still available. For example, if the Period is Weeks and you change the time aggregation to By month SUM, the Period changes to Months.

The Weeks and Quarters options are available for all visualizations that use indicator data and have a Period setting, not only for period over period comparison.

Series labels and axis labels

The legend, the tooltip, and the data table column headers use the same label for each period. The label depends on the Period unit.

Period Label format
Years Full year, such as 2026
Quarters Q, quarter number, and year, such as Q2 2026
Months Month abbreviation and year, such as Apr 2026
Weeks W, ISO week number, and year, such as W22 2026

The x-axis labels reflect the time aggregation, not the Period. The x-axis shows the position within each period.

Period Time aggregation X-axis labels
Years Daily Jan 1, Jan 2, through Dec 31
Years By week Week 1 through Week 52
Years By month Jan through Dec
Years By quarter Q1 through Q4
Quarters Daily Month 1 Day 1, Month 1 Day 2, and so on
Quarters By week Week 1 through Week 13
Quarters By month Month 1 through Month 3
Months Daily Day 1 through Day 31
Months By week Week 1 through Week 4
Weeks Daily Monday through Sunday

Settings that aren't available with period over period comparison

When Compare period over period is turned on, these settings are hidden or turned off:

  • Allow change date range
  • Show target
  • Show forecast
  • Show trend
  • Show confidence band
  • Show comment
  • Show filter as separate series

The Show threshold setting remains available.

Parent Topic:Create time series data visualizations

Keywords period over periodtime seriesindicatorcompare periods
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