Bonjour,
Un code pour le principe, à adapter à ta situation.
J'ai considéré 9600 lignes sur 9 colonnes, soit 86400 mesures.
Cdlt
Option Explicit
Public Sub test()
Dim i As Long, lig As Long
Dim rng As Range
Dim j As Byte, col As Byte
With Application
.Calculation = xlCalculationManual
.ScreenUpdating = False
End With
col = 1
For j = 11 To 19
lig = 1
For i = 1 To 9600 Step 60
Set rng = Range(Cells(i, col), Cells(i + 59, col))
Cells(lig, j) = WorksheetFunction.Average(rng.Value)
lig = lig + 1
Next
col = col + 1
Next
Application.Calculation = xlCalculationAutomatic
End Sub