Hello Joseph,

You already got many good suggestions on how to solve your task.

If you like your original code corrected:
Sub manhours_cal_corr()


'declaration
Dim resource As String
Dim trade As String
Dim labour As String
Dim labour1 As String
Dim cell As Object
Dim total As Integer
Dim count As Integer
Dim num As Integer


Sheets("Data").Select
Range("E2:E1000").Select
Selection.SpecialCells(xlCellTypeConstants, 23).Select
For Each cell In Selection
resource = cell.Value
If resource = "" Then
total = 0
Else
For count = 1 To 10
num = InStr(1, resource, ",")
trade = Left(resource, num)
If num = 0 Then
count = 11
trade = resource
End If
'MsgBox ("Resource: " & resource)
resource = Right(resource, Len(resource) - num)
num = InStr(1, trade, "[")
'MsgBox (num)
If num < 1 Then
labour1 = 100
Else
'MsgBox (trade)
labour = Right(trade, Len(trade) - num)
'MsgBox ("Labour: " & labour)
If labour < "" Then
labour1 = Left(labour, InStr(1, labour & "%", "%")
- 1)
'MsgBox ("Labour1: " & labour1)
End If
End If
total = total + (labour1 / 100)
'MsgBox ("Total: " & total)
Next count
End If
cell.Value = total
total = 0
Next cell
End Sub

Regards,
Bernd