SELECT country FROM stadium EXCEPT SELECT country FROM stadium WHERE opening_year  >  2006
SELECT country FROM stadium EXCEPT SELECT country FROM stadium WHERE opening_year  >  2006 <table_name> : stadium col : ID | name | Capacity | City | Country | Opening_year row 1 : 1 | Nou Mestalla | 75000 | Valencia | Spain | 2004 row 2 : 2 | Gazprom Arena | 69501 | Saint Petersburg | Russia | 2005 row 3 : 3 | Baku Olympic Stadium | 68000 | Baku | Azerbaijan | 2005 row 4 : 4 | Estadio La Peineta | 67500 | Madrid | Spain | 2005 row 5 : 5 | Ferenc PuskÃ¡s Stadion | 65000 | Budapest | Hungary | 2006 row 6 : 6 | Stade des LumiÃ¨res | 61556 | Lyon | France | 2004 row 7 : 7 | Northumberland Development Project | 56250 | London | England | 2006 row 8 : 8 | Fisht Olympic Stadium | 47659 | Sochi | Russia | 2004 row 9 : 9 | Arena Baltika | 45015 | Kaliningrad | Russia | 2007 row 10 : 10 | Yubileyniy Stadium | 45015 | Saransk | Russia | 2005
col : Country row 1 : Azerbaijan row 2 : England row 3 : France row 4 : Hungary row 5 : Spain