Extract four numbers without brackets from a bracketed entry, if entry exists - regex

Question

What I have:
A list of about 1000 titles of reports in column B.
Some of these titles have a four digit number surrounded by brackets (eg: (3672)) somewhere in a string of text and numbers.
I want to extract these four numbers - without brackets - in column C in the same row.
If there is no four digit number with brackets in column B, then to return "" in column C.
What I have so far:
I can successfully identify the cells in column B which have four digits surrounded by brackets. The problem is it returns the whole title including the four numbers.
Taken from: VBA RegEx extracting data from within a string
NB: I am Using Excel Professional Plus 2010, have checked the box next to "Microsoft VBScript Regular Expressions 5.5".
Sub ExtractTicker()
Dim regEx
Dim i As Long
Dim pattern As String
Set regEx = CreateObject("VBScript.RegExp")
regEx.IgnoreCase = True
regEx.Global = True
regEx.pattern = "(\()([0-9]{4})(\))"
For i = 2 To ActiveSheet.UsedRange.Rows.Count
If (regEx.Test(Cells(i, 2).Value)) Then
Cells(i, 3).Value = regEx.Replace(Cells(i, 2).Value, "$2")
End If
Next i
End Sub

Answer 1

Try
regEx.pattern = "(.*\()([0-9]{4})(\).*)"
the .* and the start and end of the string ensure you capture the entire string, then this is fully substituted by the 2nd submatch ([0-9]{4})
To fully optimise the code
use variant arrays rather than ranges
setting Global and IgnoreCase is redundant when you are running a case insensitive match on the full string
you are using late binding so you dont need the Reference
code
Sub ExtractTicker()
Dim regEx As Object
Dim pattern As String
Dim X
Dim lngCNt As Long
X = Range([b1], Cells(Rows.Count, "B").End(xlUp)).Value2
Set regEx = CreateObject("VBScript.RegExp")
With regEx
.pattern = "(.*\()([0-9]{4})(\).*)"
For lngCNt = 1 To UBound(X)
If .Test(X(lngCNt, 1)) Then
X(lngCNt, 1) = .Replace(X(lngCNt, 1), "$2")
Else
X(lngCNt, 1) = vbNullString
End If
Next
End With
[c1].Resize(UBound(X, 1), 1).Value2 = X
End Sub