A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
The reason is pretty simple: What you paste into excel is a text, not a value.
You can try to use TextToColumns to convert the text into values.
Convert numbers stored as text to numbers - Office Support
If that doesn't work means there are some invisible chars in the data, if you copy data from websites in many cases there is an ASCII 160.
In this case paste the data into an other sheet and call the UDF below to convert the text into numbers.
Andreas.
Function JustDecimalNumbers(ByVal What As String) As String
Dim i As Long, j As Long, Digit As String
Static Sep As String
If Len(Sep) = 0 Then Sep = Application.International(xlDecimalSeparator)
For i = 1 To Len(What)
Digit = Mid$(What, i, 1)
If Digit Like "#" Then
j = j + 1
Mid$(What, j, 1) = Digit
ElseIf Digit = Sep Then
j = j + 1
Mid$(What, j, 1) = Digit
End If
Next
JustDecimalNumbers = Left$(What, j)
End Function