This is a penalty kill stat in which the player clears the puck out of the zone or carry's the puck out of the zone during the penalty kill. Its an obvious tactic by the penalty kill team to try to kill as many seconds during the opposing team power play.
In relation to the penalty kill % , I think if you are going to evaluate a penalty kill you should include how many short handed goals a team scores. Interesting the Toronto Maple Leafs leads the NHL in shorthanded goals this year.
Such stats are most likely tracked and compiled by analytics organization such as SportLogiq using advanced computer vision technologies. Obviously - what SportLogiq and other such organizations track isn't available to the general public.
That said, there are some individuals in the advanced stats community who have been working on tracking transition metrics such as zone exits. They do not track every single game obviously, and I think the person behind All Three Zones (probably the most popular) only tracks at 5v5. It's something that they track manually.
All Three Zones by Corey Sznajder
www.allthreezones.com
From a scoreskeeper perspective, to make this public, it's really not as simple when you already consider all the other stuff they have to take note off. There would also be a LOT of bias in this, since you'd have someone different doing it in each arena. Scorekeeper bias is already a documented phenomenon with shots, shot attempts, shot locations, hits, blocked shots, etc. but it would probably be even worse for transition stuff. Even if it's just compiled on the PK - what you have to ask before investing the resources needed to make this possible is if it actually provides anything of value. Considering the small sample size that SH time constitutes over a season, and all the already existing metrics (and advanced metrics), I really don't see the value justifying the means. Whether your PK is successful because you block far more shots than expected, because you are successful in blocking passing lanes and shutting down cycles, because you force shots from the outside, because you limit the number of opportunities your opponent has to shoot the puck, etc. are all stuff that is already available. "SH Clears" would be a stat that would most likely highly correlate with Shots Against/60 (which is also affected by other stuff obviously).
I won't lie that it would be great, as fans, to be able to know every single driver of team performances. I'm personally very big on transition microstats (as compiled by All Three Zones notably - it's a fantastic resource and a great work that Corey Sznajder does) at 5v5, and do feel this is a component of the game that many, many fans completely forget about or under estimate when evaluating defensive play, especially. One notable example I can bring as a Habs fan is with Brett Kulak, who many thought was awful defensively. Yet, year after year with the Habs, he always had some of the best defensive metrics on the team, even if you isolated opposition by quality. He even was regularly top 25-30% amongst the league's dmen in xGA/60. And the thing is - yes, he was not "godly" defensively in his own zone, but he provided a ton of defensive value via zone entry denials AND via successful zone exits.
So yeah, I'd like to see that as an official stat, but in the end, that's a lot of ressources needed even if just applied for zone exits on the PK, there would be a lot of inaccuracies due to difference in scoreskeepers' judgments, and it's something that would be very hard to project due to small sample sizes (i.e. number of times shorthanded). It would probably have more value as a team stat as PK success/failure is far more driven by coaching and team strategy than by the individuals on the ice (to answer
@Akrapovince).