Looks like we are looking at Firearm related deaths. It is misleading to equate these numbers with the atrocities of Sandy Hook, etc., and then insinuate if we had more gun control or no guns at all these mass shootings would not happen. Although what else is new?
A few quotes from
http://www.thegatewaypundit.com/2016/02/liberal-media-gun-grabbers-ignore-latest-cdc-report-doesnt-fit-narrative/
Firearm related deaths totaled 33,636 in 2013. Of those, 21,175 were suicide, 505 were accidental discharges, and 11,208 were assault related (homicide). There were 516 legal intervention deaths, but the report does not specify how many those were firearm related.
Not even the CDC considers gun violence to be its own category
31,240 people died in accidental falls. You are more likely to die by slipping on ice than you are by someone shooting you.