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2 min read

A guide to reference lines and bands in Looker Studio

Google had previously introduced the horizontal reference lines feature in Looker Studio, which allowed marketers to create preset values to compare with actual values.

Now, Google has just launched a new feature that allows us to create vertical reference lines and bands, which will be helpful for highlighting marketing activities in reports.

Reference lines

Unlike usual horizontal reference lines, you can only use vertical reference lines in ‘Time Series’ charts with the ‘Date’ value. These are helpful for highlighting any important dates for your marketing activities. There are several types of marketing reports that we can utilise these features. For example: 

  • New product launch: You are launching a new product line and would like to track the increase in total weekly sessions going to your website after the date.
  • Creative campaigns live: Your creative campaign just goes live, and want to see the increase of clicks from brand queries on Google searched by ‘Date’. 

Reference bands

Vertical reference bands

Similar to the vertical reference line, this feature can only be applied for ‘Time Series’ charts with a ‘Date’ dimension. They are useful in highlighting a period of time, such as a promotion or sale.

Horizontal reference bands

With the Y-axis, we can now create reference bands to highlight a range of values. This feature can be applied to several chart types, including ‘Time Series’, ‘Bar’, and ‘Area’. You can use this to highlight a particular range, such as the PPC daily target spend range.

How to set up reference lines and bands in Looker Studio

After identifying which reference line or band you would like to create, the next step is setting them up in Looker Studio

First, select your chart. Then, navigate to the ‘Style tab’, then choose ‘Add a reference line’ or ‘Add a reference band’.

For ‘Date’ reference lines and bands, choose the X-axis and then fill in your reference date. You can change the colour of chosen lines and ranges. For ‘Value’ reference lines and bands, choose the left or right Y-axis and select the type of reference (constant value, metric or parameter). 

Limitations of reference lines and bands

  • You can’t add a reference line to 100% stacked charts.
  • Stacked columns, stacked bars, and stacked area charts only support constant value and parameter reference lines.

Want more actionable tips and insights on all things digital marketing and measurement? Be sure to check out more of our blogs. If you have any questions about what was covered above, get in touch!