To modify the date range, or time of day that you want to view, select the Preferences toolbar icon, or activate the context menu, by pressing your right mouse button, and selecting the Preferences menu item. This will allow you to customize the settings for the chart.

In addition to your readings, the History View Chart displays a running average, calculated as the mean of selected readings within the previous fourteen days of the current reading. This running average will show the trend for your readings.

As well, a number of statistical values are displayed. The average is indicated by the line across the center of the chart, while the lines above and below this average line indicate a distance of one standard deviation on either side of the average.

The standard deviation is a population statistic if all of your readings are selected; however, if you have set the Preferences, the standard deviation is calculated for the sample.

The range bounded by one standard deviation in either direction from the average will contain approximately 80% of your readings.

The color bars across the chart show the target ranges that you set in your Preferences, allowing you to easily see which readings fall within which ranges by time of day.

Multiple instances of this chart can be displayed concurrently, allowing you to compare trends, by different times of day for example, by modifying the preferences for each chart.