SSRS - assign Moving Average Period dynamically

SSRS chart, Calculated Series 'Moving Average':

Is there any way to make the 'Period' formula parameter dynamic? (depend on a report parameter or a query?)

My goal is to create a trend line (a smooth line chart type), therefore the 'Period' close to the total number of x-axis values on the chart, is what I need.  But the number of values can vary from 1 to hundreds, so I cannot set a fixed 'Period'.

Thanks.