Repeating Macro

Hi

I have the following macro

PHP Code: 

Sub Macro2()
'
' Macro2 Macro
'

'
    Range("B1:D1").Select
    Selection.AutoFill Destination:=Range("B1:D2"), Type:=xlFillDefault
    Range("B1:D2").Select
End Sub 


I need something on the end of this macro to make it repeat itself all the way down column B for a set number of rows. Im sure this is simple but cant seem to get it.