Re,
Ci-dessous, la procédure VBA.
ALT F11 pour ouvrir l'éditeur VBE. Voir Module1.
Cdlt.
Option Explicit
Public Sub Sum_Red()
Dim lastRow As Long
Dim Cell As Range, rng As Range
Dim N As Double, NN As Double
With ActiveSheet
lastRow = .Cells(.Rows.Count, 1).End(xlUp).Row
Set rng = .Cells(2, 1).Resize(lastRow - 1)
For Each Cell In rng
If Cell.Interior.Color = vbRed Then
'Nombre
N = N + 1
'Somme
NN = NN + Cell.Value
End If
Next Cell
.Cells(2, 4).Value = N
.Cells(3, 4) = NN
End With
End Sub