主题：谁会做这个统计

DataTables("统计").DataRows.Clear
Dim Arys As List(Of String())
Arys = DataTables("入仓").GetValues("月份|型号|规格")
For Each Ary As String() In Arys
    Dim r As Row = Tables("统计").AddNew
    r("月份") = Ary(0)
    r("型号") = Ary(1)
    r("规格") = Ary(2)
Next
Dim dt As DataTable = DataTables("入仓")
Dim dt1 As DataTable = DataTables("出仓")

For Each dr As DataRow In DataTables("统计").DataRows
    Dim Filter As String = "型号 = '" & dr("型号") & "' and 规格 = '" & dr("规格") & "'"
    dr("上月结存") = dt.Compute("Sum(入仓)",Filter & " And 月份 < '" & dr("月份") & "'") - dt1.Compute("Sum(出仓)",Filter & " And 月份 < '" & dr("月份") & "'")
    dr("本月入仓") = dt.Compute("Sum(入仓)",Filter & " And 月份 = '" & dr("月份") & "'")
    dr("本月出仓") = dt1.Compute("Sum(出仓)",Filter & " And 月份 = '" & dr("月份") & "'")
    dr("本月结存") = dr("上月结存") + dr("本月入仓") - dr("本月出仓")
Next