How to Update the access table rows with relative rows from another table

[tnncprojects]

Dear all...
After trying and find the below update query but i am not able to achieve what i required.

Dim conn1 As New OleDbConnection("My Connection String")

Dim query1 As String = "UPDATE CashDepositTran SET CashDepositTran.WidrawAmt  = CashDepositTran.WidrawAmt  - '" & outPutString & "' WHERE CashDepositTran.CTranID IN (1,2)"

Dim Cmd1 As New OleDbCommand(query1, conn1)
conn1.Open()
With Cmd1
.ExecuteNonQuery()
End With
Cmd1.Dispose()
conn1.Close()

After excuting the UPDATE query its updating by concatenate the output values (mentioned bold in table)

Table: CashDepositTran (Before UPDATE Query)
CTranID | CRegID | CashDepDate | UserID | DepAmt | WidrawAmt
1 | 1 | 09/Mar/2013 | 123 | 10000 | 10000
2 | 1 | 09/Mar/2013 | 123 | 500 | 500

10000500 and updating in each rows as below

Table: CashDepositTran (After UPDATE Query)
CTranID | CRegID | CashDepDate | UserID | DepAmt | WidrawAmt
1 | 1 | 09/Mar/2013 | 123 | 10000 | -9990500
2 | 1 | 09/Mar/2013 | 123 | 500 | -10000000