In a line graph, the horizontal axis traditionally indicates what aspect?

In a line graph, the horizontal axis typically represents the passage of time. This is a critical aspect when analyzing data because it allows observers to see how behavior or performance changes over time. For instance, when tracking a student’s progress, the horizontal axis can show different time intervals such as days, weeks, or months, allowing a clear visualization of trends, patterns, and any fluctuations in the data as time goes on.

This arrangement effectively communicates the relations between different data points, enabling practitioners to make informed decisions based on the timing and effectiveness of interventions. By aligning data with specific timeframes, it's easier to determine if a behavior is improving, deteriorating, or remaining stable over the observed period.