Islamic State's self-proclaimed 'caliphate' - the area within Syria and Iraq that the group controls - shrunk by more than 12,000 square kilometres in 2015, says military analyst, Jane's.
The loss of 14 per cent of its territory reduces the caliphate to 78,000 square kilometres.
Main losses are large swathes of Syria on its northern border with Turkey, and in Iraq the city of Tikrit, a stretch of the main highway between Raqqa and Mosul and the recent government’s re-capture of Ramadi.
The loss of land in Syria has cut off the group's main access point into Turkey, while the loss of the highway has complicated the transfer of goods and fighters between the two cities.
IS made gains by advancing further into Syria via Palmyra, but these were made at the expense of losing northern Syria to the Kurds, who, Jane's says, are the "biggest winners in 2015, expanding territory under their control by 186 per cent to 15,800 square kilometres". The Kurds are the largest component of the Syrian Democratic Forces being nurtured to form part of the US ground campaign against IS in 2016.
A UN report in September revealed that ISIS is expanding its presence in Afghanistan as it actively recruits followers in nearly three-quarters (25) of the country’s 34 provinces.