What does it mean when the previous year field is empty in Power BI?

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When the previous year field is empty in Power BI, it means that there is no data available for the previous year. This can happen for a variety of reasons, such as incomplete data or when the data source has not been updated with the previous year's data. Alternatively, the previous year field may be intentionally left blank if the user wants to compare current year data to an earlier baseline year.