ms chart moving average - There are not enough data points for the Period.

System.ArgumentException: 'Formula error - There are not enough data points for the Period.'

https://social.msdn.microsoft.com/Forums/vstudio/en-US/ee0c26da-6e45-4186-9fca-79e1ac37ed7e/problem-using-datamanipulator-moving-average-for-chart?forum=MSWinWebChart

chtEquityCurve.DataManipulator.FinancialFormula(FinancialFormula.ExponentialMovingAverage, "21", "Balance", "EMA (21)");