Sub aa()
Dim R As Range
Dim var
Dim i&
Dim g&
Dim maDate As Date
Set R = Range("a1:a" & [a65536].End(xlUp).Row & "")
var = R
For i& = 1 To UBound(var, 1)
If Not IsDate(var(i&, 1)) And IsNumeric(var(i&, 1)) Then
g& = i& + 1
If g& > UBound(var, 1) Then Exit For
Do Until Not IsDate(var(g&, 1))
If maDate = 0 Then
maDate = var(g&, 1)
Else
If maDate > var(g&, 1) Then maDate = var(g&, 1)
End If
g& = g& + 1
If g& > UBound(var, 1) Then Exit Do
Loop
If maDate > 0 Then
var(i&, 1) = maDate
maDate = 0
End If
End If
Next i&
'--- Inscription en colonne C ---
Set R = R.Offset(0, 2)
R = var
End Sub