VBA code delete the row of noisy data - vba

Question

Sub project()
Dim a, deltat_value1, deltat_value2, deltat_value3 As Integer
a = 2
Do
deltat_value1 = Cells(a, 7).Value
deltat_value2 = Cells(a + 1, 7).Value
deltat_value3 = Cells(a + 2, 7).Value
If Abs(deltat_value1 - deltat_value2) > 5 And Abs(deltat_value2 - deltat_value3) > 5 Then
Rows(a + 1).EntireRow.Delete
End If
a = a + 1
Loop Until deltat_value1 = 14700
End Sub
I am trying to delete the noisy data, I set if a data point that it has a difference bigger than 5 from both the points above and below it, that is a noisy data and I set to delete the whole row of the noisy data.
However, I am having this problem for the line:
deltat_value3=Cells(a+2,7).Value
Runtime Error 1004 "Application-defined or Object-defined error"
And the running takes extremely longer time. I am a new user of VBA programming and I think my method may be inefficient, there may be other ways work much better, any advice?

Answer 1

How about:
Sub ytrewq()
Dim a As Long, deltat_value1 As Long, deltat_value2 As Long, deltat_value3 As Long
Dim rKill As Range
a = 2
Do
deltat_value1 = Cells(a, 7).Value
deltat_value2 = Cells(a + 1, 7).Value
deltat_value3 = Cells(a + 2, 7).Value
If Abs(deltat_value1 - deltat_value2) > 5 And Abs(deltat_value2 - deltat_value3) > 5 Then
If rKill Is Nothing Then
Set rKill = Cells(a + 1, 1)
Else
Set rKill = Union(rKill, Cells(a + 1, 1))
End If
End If
a = a + 1
Loop Until deltat_value1 = 14700
rKill.EntireRow.Delete
End Sub