Hire Power BI developer uses DAX (Data Analysis Expressions) to create complex calculations and custom measures that enhance data analysis. With DAX, developers can filter, group, and summarize data in ways that standard formulas can’t achieve. This allows for more dynamic and insightful reports, providing deeper insights into trends, performance metrics, and key business indicators. DAX also allows developers to create time intelligence calculations, such as year-over-year comparisons or cumulative totals, which provide valuable insights for strategic decision-making. A skilled developer ensures that DAX is used to optimize data models for efficient analysis.