What type of visual is best for showing trends over time in Power BI?

A line chart is the most effective visual for displaying trends over time because it connects individual data points with lines, allowing viewers to easily see changes and patterns over a specific time period. This type of visualization emphasizes the continuity of data points, making it straightforward to analyze trends, fluctuations, and overall movements in the data as time progresses.

When it comes to comparing data over time, line charts can illustrate multiple series simultaneously, facilitating the comparison of trends between different data sets. They are well-suited for showing how values rise and fall, which is crucial for time series analysis.

Other types of visuals, such as maps, pie charts, and bar charts, serve different purposes. Maps are best for geographical data representation, pie charts are used for displaying proportions rather than trends, and bar charts can show changes over time but are less effective than line charts for visualizing continuous data because they break the data into discrete categories rather than presenting a flow. Thus, for analyzing trends over time, a line chart provides the clarity and functionality needed.