GroupBY and summarize

Hi MlleEllaZ00,

The behavior you’re noticing is caused by how the column is defined in the model, not just the Group By function. In Power BI, numeric fields are automatically aggregated, but this depends on the column’s data type and default summarization setting. If your column is set as text or to Don’t summarize, it acts as a dimension and won’t aggregate, which is why your colleague can summarize it but you can’t. This can happen even if you’re using the same file because of model-level settings. Make sure the column data type is numeric and the default summarization is set to options like Sum or Average.

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Thank you.