(Muslim Press) - According to IHS Jane ' s report, ISIS ' " Caliphate " has shrunk by approximately 13,000 square kilometers since January, which is a net loss of 14 percent.The terrorists have lost large areas of Syria’s northern border with Turkey, including the Tal Abyad border crossing, that was the group’s main access point to the Turkish border from their de - facto capital Raqqa, IHS Jane ' s Defense Weekly guide to international weapons technology and military defense news reported. In Iraq, ISIS terrorists ' losses include the city of Tikrit, the Beiji refinery complex, and a stretch of the main highway between Raqqa and Mosul, complicating the transfer of goods and fighters between the two cities.Recommended:Iraq working with Russia, Iran and Syria to defeat ISIS The ISIS terrorists' advance into western Syria and the capture of Ramadi’s city center in May came at the expense of losing northern Syria to the Kurds. Syria’s Kurds are by far the biggest winners in 2015, expanding territory under their control to almost 16,000 square kilometers and establishing control over nearly all of Syria’s traditionally Kurdish areas, according to the report.