--Using LINQ
var v = (from o in dt.Rows.Cast()
select o.Field("Grand Total")).Average();
--Using Datatable Compute Method
Object objAvg;
objAvg = dt.Compute("Avg([Grand Total])", "[Grand Total] > 0");
--Find Standard Deviation using Datatable Compute method
Object objStDev;
objStDev = dt.Compute("StDev([Grand Total])", "[Grand Total] > 0");
var v = (from o in dt.Rows.Cast
select o.Field
--Using Datatable Compute Method
Object objAvg;
objAvg = dt.Compute("Avg([Grand Total])", "[Grand Total] > 0");
--Find Standard Deviation using Datatable Compute method
Object objStDev;
objStDev = dt.Compute("StDev([Grand Total])", "[Grand Total] > 0");