Mu buryo bworoshye kumva, ubukene bwari kuba bwaragabanutse kuri icyo gipimo kinini gutya mu gihe igiciro cyo kubaho ku ngo 40% zikennye cyane cyari kuba cyarazamutse ku rwego rwa 4,7% hagati y'ukwezi kwa mbere 2011 n'ukwa mbere 2014.
