Formule dans cellule Vba

Sub Creation_Calendrier()
Dim rep As Variant
Dim chemin As String
Dim Mois As String
rep = InputBox("Quelle année d'exercice?")
cemin = "C:\Users\Sandrine\Desktop\PERSO\SOCIETE\Suivi SJTC"
Worksheets(Array("Consolidé", "Facturation")).Copy
ActiveWorkbook.SaveAs Filename:=cemin & "\Exercice SJT-C " & rep & ".xls", FileFormat:=52
Workbooks("Exercice SJT-C " + rep).Worksheets("Consolidé").Activate

Cells(2, 2).Value = "Janvier " + rep
Cells(2, 6).Value = "Fevrier " + rep
Cells(2, 10).Value = "Mars " + rep
Cells(2, 14).Value = "Avril " + rep
Cells(2, 18).Value = "Mai " + rep
Cells(2, 22).Value = "Juin " + rep
Cells(2, 26).Value = "Juillet " + rep
Cells(2, 30).Value = "Aout " + rep
Cells(2, 34).Value = "Septembre " + rep
Cells(2, 38).Value = "Octobre " + rep
Cells(2, 42).Value = "Novembre " + rep
Cells(2, 46).Value = "Décembre " + rep
Cells(2, 50).Value = "Totaux " + rep
Mois = Cells(2, 2).Value
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Janvier " + rep
With Sheets("janvier " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Fevrier " + rep
With Sheets("Fevrier " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Mars " + rep
With Sheets("Mars " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Avril " + rep
With Sheets("Avril " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Mai " + rep
With Sheets("Mai " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Juin " + rep
With Sheets("Juin " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Juillet " + rep
With Sheets("Juillet " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Aout " + rep
With Sheets("Aout " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Septembre " + rep
With Sheets("Septembre " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Octobre " + rep
With Sheets("Octobre " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Novembre " + rep
With Sheets("Novembre " + rep)
Call conception_feuille
End With
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = "Décembre " + rep
With Sheets("Décembre " + rep)
Call conception_feuille
End With
Sheets("Consolidé").Select
'Cells(5, 2).FormulaLocal = "='sheets(Janvier "& rep")'!R[3]C[27]"

ChDir "C:\Users\Sandrine\Desktop\PERSO\SOCIETE\Suivi SJTC"
End Sub

Dim mois As String
Dim rep As Long
Dim f As String
rep = 2021
mois = "Janvier"
f = "='" & mois & "-" & rep & "'!R[3]C[27]"
Cells(5, 2).Formula = f

Sheets("Consolidé").Select

Cells(5, 2).Formula = "='" & MonthName(1) & " " & rep & "'!R[3]C[27]"
Cells(5, 3).Formula = "='" & MonthName(1) & " " & rep & "'!R[3]C[27]"
Cells(5, 4).Formula = "='" & MonthName(1) & " " & rep & "'!R[3]C[27]"