4 - The Capitals’ goal differential on the power play so far this year (five goals for, one against). That’s the second-worst in the League, trailing only Ottawa’s +3 with the man advantage.
This all feeds into the larger trend (and one that has persisted for a fairly long time) of the power-play struggles for the Caps, a once dominant team with the extra man.
Cause for concern? You be the judge.