# Timeline graphs

The timeline graph is used when you are comparing time (dates). A timeline shows fluctuations in a single metric (e.g., estimated earnings) for two different date ranges or multiple metrics for a single date range. You can switch between viewing activity by days, weeks or months using the new DayWeek and Month buttons. The "Month" button is particularly useful for reducing noise when you’re viewing reports with a long time line, such as an “All time” report.

This graph exhibits quantitative information or illustrates relationships between two changing variables (a time series) with a line that connects a series of data points. A line graph can identify trends, and shows an increasing, decreasing, fluctuating, or remaining ‘constant rate of change’.

The timeline is presented in two views:

• If one metric is selected, then the data is shown as a single line graph with a shaded area.
• If more than one metric is selected, then the data is shown as multiple line graphs with no shaded areas.
‘Show events’ displays historical changes to your account which are time-based. Therefore, the ‘Show events’ checkbox is only available for the “Timeline” chart.

## X-, Y1- and Y2-axes

To help you read a graph and measure the information, graphs are plotted with the use of X and Y axes.

The X-axis is the line on the graph that runs horizontally from left to right. As value x increases, the point on the graph moves further right.

The Y-axis is the line on the graph that runs vertically from the bottom up. As the value of y increases, the point on the graph moves further up.

All measurements start from the value of zero where the X and Y axes intersect.

A Y2-axis is displayed as a second vertical line which appears on the right side of the graph. The Y2-axis enables you to see two sets of data on a single graph even when the values measured are different.

• X-axis: Represents the selected date range displayed as month and date.
• Y1-axis: In order of selection, the graph uses the first chosen metric as its value.
• Y2-axis: In order of selection, the graph uses the second chosen metric as its value.
For example, let’s say you selected to run the ‘Entire account by day’ report. You want to see a report for activity on your entire account by day. The days are shown on the X-axis. You decide to display multiple metrics: Clicks and CPC, the Y-axis displays monetary values. The Y2-axis displays the CPC numerical values. Each line represents a selected metric; the color of the metric matches the color of the line graph.

## Rollover effect

Read along the X-, Y1- and Y2-axes. If you mouse over a point of intersection in the line graph, a statistical bubble appears with information about the metrics you have selected for that specific intersection in the report and the date for that point on the graph.