The pdf linked from Jérôme's link includes a graph showing the last three years and this year with the quartals in different colours. Apparently, the trend is not so clear there: in 2007 and 2009, Q3 was equally strong; in 2008, Q3 was weak and all the others equally strong (while total annual installations showed a steady moderate increase).

_{*Lunatic*, n.
One whose delusions are out of fashion.}