Cumulative Charts - Cumulative Sum
If you want to create a cumulative chart to visually track the total progress or accumulation of data over time, utilize the Cumulative mode available in Performance Objectives, Performance Trend, Multi Metric Combined Chart, and Multi Metric Trend Chart dashboard gadgets. The cumulative mode becomes available when a date type field is selected for the 'Display by' setting.
In the image below, you can observe how the default plain mode displays data versus the cumulative mode applied to the same data.