What type of data visualization is best used for showing trends over time?

Line graphs are particularly effective for showing trends over time because they connect individual data points with lines, providing a clear visual representation of movement between those points. This allows viewers to easily discern patterns, fluctuations, and trends over a continuous period. When data is plotted in a line graph, it’s straightforward to observe increases or decreases over time, making it suitable for time series analysis where the chronological order of data is crucial.

Bar graphs, while useful for comparing discrete categories, do not effectively convey trends over time since they focus on separate bars rather than a continuous flow of data. Pie charts are designed to show proportions of a whole at a single point in time and do not reflect changes or trends. Scatter plots can show relationships between two variables, but they are not optimized for illustrating how a variable changes over time. Therefore, line graphs are the preferred choice for depicting temporal trends.