Find Next Function with two criteria Help

Wow, over 6 hours! I'm not sure I know of a way to make it quicker. Hopefully someone else with more knowledge will have a solution. Oddly though, I would think that with only 75500 checks it wouldn't take that long at all. Have you tried adding Exit Sub after Then and before Else? Hmm....maybe change your code to this instead....

Sub GoalSeek()
 Dim i As Long
 
 Application.ScreenUpdating = False
 For i = 5 To 75500
 If (Range("Z" & i) <> 12 Or Range("Z" & i) <> "") Then
 With Range("Z" & i)
 .GoalSeek Goal:=12, ChangingCell:=Range("X" & i)

 Else
 Exit Sub

 End With
 End If
 Next i
 
 Application.ScreenUpdating = True
 End Sub

Edit* Not sure if this code will work at all...in my head it works perfectly.