Hi Harward thanxs for reply. it give me following message when i using MaxID=Max(T.ID) _ Error Message. Overload resolution failed because no accessible 'Max' can be called without a narrowing conversion: Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Decimal?)) As Decimal?' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Decimal?'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Decimal)) As Decimal' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Decimal'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Double?)) As Double?' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Double?'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Double)) As Double' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Double'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Single?)) As Single?' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Single?'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Single)) As Single' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Single'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Long?)) As Long?' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Long?'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Long)) As Long' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Long'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Integer?)) As Integer?' defined in 'System.Linq.Enumerable': Return type of nested function matching parameter 'selector' narrows from 'Object' to 'Integer?'. Extension method 'Public Function Max(selector As System.Func(Of <anonymous type>, Integer))