Why can’t I create a year-on-year comparison in Looker Studio?

Usually you can’t create a year-on-year comparison in Looker Studio because the previous year holds no data, not because the feature is missing. Looker Studio, since April 2026 called Data Studio again, offers Previous year as a comparison date range, but Search Console keeps only 16 months of data, and a GA4 property only reaches back to the day it started collecting.

Google dates the rebrand to 16 April 2026 in its release notes; existing reports and links keep working. The second common cause is the setup: the comparison is set per chart, only by editors, and only on chart types that support it.

How do you set up a year-on-year comparison in Data Studio?

1. Open the report in edit mode and select a time series, table, area chart or scorecard – the chart types for which Google’s date range guide documents the option.
2. In the properties panel, open the Setup tab and go to the default date range section.
3. Under Comparison date range, choose Previous year and click Apply.
4. Check the result: a time series shows the previous year as a second line in another colour, a table shows the change with an up or down indicator.

Viewers can still change the current period with a date range control, and the comparison follows it. Google’s own example compares 25–31 December 2018 with 25–31 December 2017. Only editors can change the comparison setting itself.

Previous year compares calendar dates, so weekdays shift. For daily charts, use the advanced date settings and set the comparison 364 days back – exactly 52 weeks – so Monday meets Monday.

Why does the previous year stay empty?

• Search Console keeps 16 months. Google states this in its Analytics Help on the Queries report, which draws on the same data. The Search Console connector cannot fetch older days.
• The GA4 property is younger than the comparison period. Two of our client properties were only created on 24 and 25 November 2025, so any comparison period before that is empty.
• Not the GA4 retention setting. Retention of 2 or 14 months applies to explorations and funnel reports; Google says it does not affect standard aggregated reports (data retention). Data Studio queries GA4 through the Data API. We tested a service business whose property is set to two months: the API still returned 651 sessions for 23 July to 20 October 2024 and 531 for the same period in 2025.
• No valid date field. A Sheets or CSV source needs a date dimension with year, month and day. A column with “2025-05” or dates stored as text cannot drive a date range.

Does the year-on-year comparison work with our own Search Console data?

On 22 October 2026 the Search Console API returned these web-search figures for 1hold.de:

The autumn comparison works: 223 clicks against 23, and 51,526 impressions against 8,544, about six times as many. May does not. May 2026 had 106 clicks and 21,962 impressions, but the oldest day the API still returned was 9 June 2025, so Previous year has nothing to compare with. June is the trap in between: June 2025 only contains the 22 days from 9 June (6 clicks, 5,139 impressions), June 2026 the full month (100 clicks, 22,733 impressions). The growth looks bigger than it was, and because the 16-month window moves forward every day, those June days will soon disappear as well.

Before you build a year-on-year chart, check the oldest date your source returns and compare only complete periods. If you need Search Console history beyond 16 months, start storing it now: the bulk data export to BigQuery starts with the day you set it up and does not backfill, so pull the available 16 months once via the API as well.

Which three checks should you make before you trust the comparison?

1. Complete periods. No partial months, and leave out the most recent days: Search Console marks its newest data as preliminary. If recent days are missing altogether, read why the data from the last few days is missing.
2. Same measurement in both years. A new consent banner, a second tracking tag or a domain move between the two periods changes the numbers without any change in demand. Note such dates in the report.
3. Same source. Compare Search Console with Search Console and GA4 with GA4. A comparison across two different GA4 properties needs a blend and a careful look at the overlap.

Sources

• Data Studio Help: Set report date ranges
• Search Console Help: Bulk data export to BigQuery
• Analytics Help: Data retention

Want year-on-year reports that show real trends instead of gaps? We set up Data Studio reports on Search Console, GA4 and Google Ads, check the data history first and store what Google deletes. Book a free initial call or see our SEM strategy and analysis services.