Which type of chart is ideal for tracking changes or numbers over time?

A line chart is the ideal choice for tracking changes or numbers over time due to its ability to clearly illustrate trends and patterns across continuous data points. The design of a line chart employs a series of data points connected by straight lines, which allows viewers to see how values increase or decrease over specific intervals. This visual representation is particularly useful when dealing with time series data, as it emphasizes the overall trajectory rather than just individual data points.

In contrast, pie charts, while effective for displaying the proportion of parts to a whole at a single point in time, do not depict changes over time. Column and bar charts are more suited for comparing categorical data or showing discrete values rather than illustrating trends in data that occurs sequentially over time. Thus, the line chart stands out as the most appropriate choice for representing shifts in data across various periods.