Date Range Comparison in Data Studio

A comparison date range lets you display a second time period alongside your primary date range on a chart or scorecard. Looker Studio calculates the difference (delta) and can show it as an absolute number or percentage change — making it easy to see whether performance improved or declined period over period.

Comparison date ranges are supported on Scorecards, Time series charts, and Tables. Bar charts, pie charts, and geo maps do not currently support this feature natively — you would need to use blended data or calculated fields for those chart types.

Looker Studio offers several built-in options: Previous period (matches the length of your primary range), Previous year (same dates one year prior), Same period last year, and Custom — where you define the exact start and end dates of the comparison window.

The comparison date range set in the SET-UP panel is a chart-level override. If you have a Date Range Control widget on your report, viewers can change the primary date range — the comparison will shift relative to whatever primary range is selected. If you want a fixed comparison, set a fixed date range on the chart instead of using the report control.

Yes. On a Scorecard, once the comparison date range is set, you can choose to display the delta as a percentage change or as an absolute value in the chart's STYLE tab. For time series charts, the comparison period appears as a second line — hover tooltips show both values side by side.

The field is greyed out when the selected chart type does not support comparisons, or when the chart's date dimension is not set. Make sure your chart has a valid date field in the Date Range Dimension slot in SET-UP. If you are in View mode rather than Edit mode, switch to Edit mode first.