I am not sure of the inferences that can be drawn from an answer nor intent and motive of the question. Or course it will depend on sources and the criteria used to deem what a terrorist organization is and what an incident is. Using Wiki as a source and others to verify the answer for the 'Questions' journey is for worldwide:
2014 - 265
2015 - 404
2016 - 1,813
2017 - 160
Total - 2,642
But, that does not paint the picture. It only is the paint used if you get the drift. There is today according to our State Dept. 251 'Foreign' terrorist organizations. Most are at odds with their state governments and/or are separatists groups. An example is from 2013 where Europol reported there were 152 terrorist attacks in Europe. Only two were religiously motived. Eighty-four were conducted by ethno-nationalist & separatist groups. As a side note try researching U.S. domestic terrorist activity.
One source shares there were 31 terrorist incidents in the U.S. beginning with 2014. A complete list beginning 1865 can be found here:
So, as seen with this small portion of a snap-shot terrorism is much more complex than the blankets we tend to use. Yes, terrorism is significant in my view. Yes, religiously motivated Islamic extremist terrorism with its history and activity is significant. But, when researched especially historically terrorism is very vast with many variables. We may even take it to the extreme that a playground bully is a terrorist can't we?