Option Explicit
Sub TotalValeur()
Dim RgeA, RgeB, RgeC As Range
Dim Total, i As Integer
Set RgeA = Sheets(1).Range("A2")
Do While RgeA <> ""
Total = 0
For i = 2 To ThisWorkbook.Sheets.count
Set RgeB = Sheets(i).Columns(1).Find(what:=RgeA.Text, LookIn:=xlValues, lookat:=xlWhole)
If Not RgeB Is Nothing Then Total = Total + Application.Sum(Sheets(i).Rows(RgeB.Row))
Set RgeC = Sheets(i).Columns(2).Find(what:=RgeA.Text, LookIn:=xlValues, lookat:=xlWhole)
If Not RgeC Is Nothing Then Total = Total + Application.Sum(Sheets(i).Rows(RgeC.Row))
Next
RgeA(1, 2) = Total
Set RgeA = RgeA(2, 1)
Loop
End Sub