A report can show what revenue would look like under a different assumption. The useful part is keeping that assumption separate from what happened. A changed number must never look like a new actual result.
Data Studio, formerly Looker Studio, supports parameters that readers can change through controls. This example uses one input to calculate a revenue scenario. It does not change the source data, and it does not predict how customers will behave.
Define the assumption before the formula
Use a hypothetical spreadsheet with one row per day. Its Date field contains two dates. Its numeric Revenue field contains €1,000 and €500. Both amounts use the same currency and revenue definition. The total is €1,500. You need permission to edit this data source.
Define the input as an assumed percentage change in revenue. Entering 10 means an increase of 10%. Entering -10 means a decrease of 10%. This convention matters: 0.10 would mean an increase of only 0.1%. A label such as “Multiplier” would hide that distinction.
A filter selects which rows contribute to a result. This parameter changes the calculation applied to those rows. Keep the original Revenue field as the actual measure. Give the calculated result a separate name, Scenario revenue, so readers can compare both values.
Create a bounded input and a separate metric
In the data source editor, add a Number parameter named Scenario_change_pct. Choose a permitted range from -50 to 50 and a default of 0. These are example input limits, not a confidence interval. Choose limits that fit the question before using this pattern in a real report. Google documents the setup in its parameters guide.
Add a data source calculated field named Scenario revenue. Use the parameter name in the formula below. The Revenue field must contain row-level numeric amounts for this example. Set both revenue metrics to Sum in the charts. This is not a recipe for mixing an already aggregated connector metric with an unaggregated field.
