📈 Power BI DAX examples

SAMEPERIODLASTYEAR Examples in Power BI DAX

Compare the current period with the same period last year. This page gives you the syntax, five practical business examples, common mistakes, and copy-ready DAX you can adapt for reports.

Updated 2026-06-125 business examplesCopy-ready DAX

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What SAMEPERIODLASTYEAR does

Compare the current period with the same period last year. In Power BI, the key is not only the formula itself but how it behaves with slicers, relationships, visuals and totals.

Syntax or pattern

SAMEPERIODLASTYEAR(dates)

✍️

5 practical business examples

1

SAMEPERIODLASTYEAR in a sales report

Calculate sales from the start of the year to the current date.

Sales LY = CALCULATE([Total Sales], SAMEPERIODLASTYEAR(Calendar[Date]))

Requires a proper marked date table.

2

Sales last year

Shift the current period to last year.

Sales LY = CALCULATE([Total Sales], SAMEPERIODLASTYEAR(Calendar[Date]))

Use this for year-over-year comparisons.

3

Previous month sales

Compare current sales to the previous month.

Sales LY = CALCULATE([Total Sales], SAMEPERIODLASTYEAR(Calendar[Date]))

Useful for monthly trend cards.

4

Rolling 12 month sales

Calculate sales over the last 12 months.

Sales LY = CALCULATE([Total Sales], SAMEPERIODLASTYEAR(Calendar[Date]))

Good for smoothing seasonality.

5

Month-to-date target check

Compare current sales against current month target.

Sales LY = CALCULATE([Total Sales], SAMEPERIODLASTYEAR(Calendar[Date]))

Use with month filters for target reporting.

Common mistakes to avoid

Using SAMEPERIODLASTYEAR before checking whether the data model has the right relationships and filter direction.
Writing one complex measure instead of creating simple base measures first.
Testing only at the total level and not checking row, category and date contexts.
Forgetting that slicers, visuals and relationships can all change the filter context.

FAQ

When should I use SAMEPERIODLASTYEAR in DAX?

Use SAMEPERIODLASTYEAR when the calculation pattern matches the business question and the result behaves correctly in the current filter context.

Why is my SAMEPERIODLASTYEAR measure returning the wrong total?

Most total issues come from row context, filter context, relationships, or using a column aggregation where an iterator or CALCULATE pattern is needed.

Can I use this SAMEPERIODLASTYEAR pattern in a calculated column?

Some patterns work in calculated columns, but most reporting calculations should be measures so they respond to slicers and report filters.