Try something like this,

Code:
    While Not rsIncome.EOF
    theRs.Find "CurrentDate=#" & CStr(rsIncome.CurrentDate) & "#", , adSearchForward, 1
    if theRs.EOF then
        theRs.AddNew
        theRs.Fields!CurrentDate = rsIncome.Fields!CurrentDate
        theRs.Fields!Income = rsIncome.Fields!Income
    else
        theRs.Edit
        theRs.Fields!Income = rsIncome.Fields!Income
    End If
    theRs.Update
    rsIncome.MoveNext
    Wend