How to get a chart's summarized data (Active visulazition) from SDK

We want to get a chart's summarised data (Active visualisation) from SDK.
We are able to get the data of the data table which is responsible to create the chart but we need to get the
summarised data only which is used to create that chart.
We need chart series data that we get after applying the expression or aggeration methods or filters and etc.. on chart.
For example- On our chart, X axis has a column name as EmployeeName. Y axis value has Sum(Salary).
Now we want to get the data of these both axis as EmployeeName and Sum(Salary).
Please create an enhancement request to get the chart series data which is made using custom expression.