I'm trying to understand exactly what happens with the data points plotted on an XY chart which uses aggregation. The documentation states,

"In order to increase performance, the chart control will automatically determine the optimal number of data points to display based on the size of the control. This is determined using the AggregationFactor property, which defaults to 0.2.

For example, if the chart control is 100 pixels wide and uses an aggregation factor of 0.1, then the optimal number of data points would be 10. If the data source contained 1000 items, then the chart would create 10 groups, each with 100 items in it. Then some sort of aggregation function would be performed on each group to generate a single data point for display."

(It then goes on to explain the aggregation function which is used.)

So say we have a chart plotting temperature against time. The data source contains the temperature for the last three hours, one point per minute, therefore 180 points. The chart is 800 pixels wide and the aggregation factor is 0.2. The "optimal number of data points" would be 160.

Does that mean that 160 data points would be plotted on the chart? How many points would be in each group? Which points would fall into which groups? And how would the data be aggregated?