You have a point, however, look at the regional data at INSEE:

1. the €1,792 billion final total quoted by FT seems to cover DOM-TOM incompletely,
   
2. using €1.32 = £1 (the current price is even below that), Metropolitan France's €1,762 billion total for 2006 equals £1,335 billion, still well ahead of the UK's £1,304 billion.