Why did new Visual Calculations appear in Power BI?
1. Background: Why It Emerged
- The Steep DAX Learning Curve
- While DAX is powerful, its syntax
is difficult.
- Advanced functions, especially
those like CALCULATE , FILTER, or SAMEPERIODLASTYEAR, were particularly
challenging for beginners to approach.
- Even for simple tasks like finding a "growth rate" or a "running total," users had to write long, complicated expressions.
- Model Registration Required Even for Throwaway Calculations
- Any calculation needed—such as
rank, difference, or cumulative total—even if it was only momentarily
required for one specific chart, had to be registered as a measure in the
data model.
- As more people created reports,
measures piled up in the model, making management complex and dragging
down performance.
- The Gap Between Analysts and Modelers
- BI developers and modelers
generally prefer "reusable measures."
- However, business analysts often
just wanted to calculate values directly from what they saw on the
screen, similar to how they work in Excel.
- Crucially, when testing hypotheses on the fly, model-level work created significant burdens in terms of time and resources.
👉 To solve these pain points, Power BI introduced "post-aggregation" calculations.
This new feature allows you to
directly calculate based on the aggregated results already shown in the visual.
It enables fast analysis without having to touch the underlying data model.
2. Core Features of New Visual Calculations
3. Here are the primary ways you can put this to use
Key Use Cases
- Rapid Comparison & Variance
Calculation
For example, you can calculate the “Year-over-Year Sales Variance” directly within a bar chart. This lets you calculate immediately using the aggregated values shown in the visual, completely bypassing the need for complex DAX.
- Ad-hoc Analysis
Before a report is distributed, analysts can quickly check temporary metrics like "growth rates," "differences," "running totals," or "ranks." The great benefit here is that unnecessary measures are prevented from cluttering the model, helping to keep it clean.
- Support for Excel-Savvy Users
Users who are already comfortable with Excel can easily apply calculation formulas. This dramatically lowers the barrier to entry for business users and allows them to perform analysis more independently.
- Visual-Specific Metrics
You can create indicators, like the "Top 3 Total" or "Top 10% Average," that are only needed for a specific chart, without having to add them to the entire data model.
4. Things to Keep in Mind (Cautions)
- Not Reusable: New Visual Calculations are confined strictly to the visual they are applied to. If you need to use the same logic repeatedly across multiple reports, pages, or visuals, creating a standard DAX measure is still the better approach.
- Limitations on Complex Logic: For highly complex logic, such as intricate multi-filtering or advanced Time Intelligence, DAX offers much greater flexibility and power.
- Performance Check: Since visual-level calculations are processed in real-time, especially with large datasets, you should periodically monitor performance to ensure everything is running smoothly.
5. Wrapping up
The new Visual Calculations feature is best viewed as an "analyst-friendly calculation tool" that neatly bridges the gap between the data model and DAX. It becomes a powerful option whenever you need to quickly generate insights without having to modify the underlying data model.<Other posts on the blog>
Standard Deviation (Part 1): Measuring Data Volatility and Using the Insights for Better Strategy
DAX CALENDAR Function Deep Dive and Practical Usage Guide
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