The GTI is produced by the Institute for Economics & Peace (IEP) based on data from the Global Terrorism Database (GTD). Data for the GTD is collected and collated by the National Consortium for the Study of Terrorism and Responses to Terrorism (START) at the University of Maryland. The GTD contains over 170,000 terrorist incidents for the period 1970 to 2017.

Deaths from terrorism fell for the third consecutive year, after peaking in 2014. The total number of deaths fell by 27 per cent between 2016 and 2017, with the largest falls occurring in Iraq and Syria. Iraq recorded over 5,000 fewer deaths from terrorism in 2017, while Syria recorded over 1,000 fewer deaths. The fall in deaths was reflected in scores on the GTI, with 94 countries improving, compared to 46 that deteriorated. This is the highest number of countries to record a year on year improvement since 2004 and reflects the increased emphasis placed on countering terrorism around the world since the surge in violence in 2013.

The large falls in the number of deaths in Iraq and Syria is mainly the result of ISIL’s continuing decline. The number of deaths from terrorist attacks attributed to ISIL fell by 52 per cent in 2017, with total incidents falling by 22 per cent. There was a corresponding decrease in the lethality of attacks, highlighting the weakening capacity of the organisation. ISIL has now lost most of its territory and sources of revenue and is actively redirecting resources away from the Middle East and into North Africa, sub-Saharan Africa, and Southeast Asia.

Despite its reduced capacity, ISIL remained the deadliest terrorist group globally in 2017. The decline of ISIL has also been reflected in the level of terrorist activity in Europe, with the number of deaths falling by 75 per cent, from 827 in 2016 to 204 in 2017. Preliminary data for 2018 suggests this trend will continue, as less than ten deaths from terrorism have been recorded in Western Europe from January to October 2018. Afghanistan was the country that recorded the highest number of terrorism deaths in 2017. The number of deaths was approximately the same as the prior year.

Angola and Spain had the largest deteriorations in score in the GTI. Angola’s score deteriorated because of a gas attack on a Jehovah’s Witnesses convention which left 405 people injured, but resulted in no fatalities. Spain’s score deteriorated because of the attacks in Barcelona in August 2017. Spain also recorded one of the five largest deteriorations on the Global Peace Index for 2017, highlighting broader concerns related to social unrest.

Although the total number of deaths from terrorism has fallen, the impact of terrorism remains widespread. In 2017, 67 countries experienced at least one death from terrorism, which is the second highest number of countries recording one death in the past twenty years. However, it is a fall from the peak of 79 countries in 2016. There were 19 countries that recorded over a hundred deaths from terrorism in 2017, and five that recorded more than a thousand.

The global economic impact of terrorism was US$52 billion in 2017, 42 per cent lower than in 2016. Compared to other forms of violence such as homicide, armed conflict, and military expenditure, terrorism is a small percentage of the total global cost of violence, which was equal to 14.76 trillion dollars (PPP) in 2017. It should be noted that the figures for terrorism are conservative as they do not account for the indirect impacts on business, investment and the costs associated with security agencies in countering terrorism. Terrorism also has wideranging economic consequences that have the potential to spread quickly through the global economy with significant social ramifications.