Why are you measuring the number of people that shoot each other, vs. the number killed? Why only look at 2015? Your statistics are just as suspect. I'd recommend reading this:
slatestarcodex.com/2016/08/31/terrorists-vs-chairs-an-outlier-story/
slatestarcodex.com/2016/08/31/terrorists-vs-chairs-an-outlier-story/
I agree with Obama's overall point about guns. But from what you've written, I'm under the impression you think he's wrong about terrorism.