Decreases were observed of more than 18% in the number of replacement primiparous gilts, and of 12% in the number of piglets of less than 20 kg live weight.
Big differences were seen between regions, with a decrease in the swine population of 11.4% in Flanders, and an increase of 1.8% in Wallonia.
http://economie.fgov.be/fr/modules/pressrelease/statistiques/economie/resultats_de_l_enquete_agricole_de_novembre_2009.jsp