[UPDATED with corrected figures. See below.]
A few weeks ago, I looked at some hypothetical levels of goaltending and puck possession to try to determine just what the impact of those aspects of play had on the Lightning’s season. From that experiment, I concluded that in order to get into playoff contention (there was still about a week of games left), the Lightning would have needed either elite goaltending (above .920) or elite puck control (over .520) or moderate improvement in both (.914 and .500).
This week, I decided to apply the same question to another area where the Lightning struggled this season: special teams. As we all know from watching the games, the power play was abysmal and the penalty kill was almost abysmal. Tampa Bay’s 15.2 % power play conversion rate and 79.2% penalty kill rate were both 26th in the league. The team’s special teams goal differential, however, was by far the worst in the league at -28, a full 10 goals from the next lowest team (the Winnipeg Jets at -18).
This was a function the extremely high number of shorthanded goals the power play unit allowed (12, or 29th in the league), plus that very low conversion rate, plus that very low penalty kill rate, plus a very low number of shorthanded goals for. In other words, the Lightning’s special teams stunk all around.
Surely fixing that power play would have put the Lightning in playoff contention? Well, not really.
To get a better picture of how special teams affected the team’s fortunes, I first addressed the impact of shorthanded goals (both for and against), using what I’m calling the Effective Power Play (or Penalty Kill) Rate.
Effective PP% = [(PPG-SHGA)/ PPOpps]*100 = takes into account the number of times the power play unit(s) gave up shorthanded goals against to get a picture of the real impact of the power play on goal differential
Effective PK% = [1-(PPGA-SHGF)/TS)]*100 = takes into account the number of times the penalty kill unit(s) scored shorthanded goals for to get a picture of the real impact of the penalty kill on goal differential
|
Official Tampa Bay Power Play rate via NHL.com |
15.2 |
|
Power play opportunities |
269 |
|
Power play goals |
41 |
|
Shorthanded goals against |
12 |
Effectively the Lightning operated at a 10.8% Power Play rate.
On the penalty kill:
|
Official Tampa Bay Penalty Kill rate via NHL.com |
79.2 |
|
Times Shorthanded |
284 |
|
Power Play goals against |
59 |
|
Shorthanded goals for |
2 |
Effectively the Lightning operated at a 79.9% Penalty Kill rate.
Sorting the teams by their effective rates puts the Lightning dead last in the league in Effective Power Play numbers and 27th in the league in Effective Penalty Kill numbers.
So, what would have happened if the Lightning’s special teams rates were different, but nothing else (number of power plays or times shorthanded, even strength goals for or against) changed? What would really have changed the Lightning’s fortunes?
The following chart shows the power play and penalty kill rates for the Lightning last season and for the league this season, and the results (in total goal differential) of applying these rates to the season.
|
Power Play |
Penalty Kill |
GD w this PP |
GD w this PK |
GD w both |
|
|
TBL 2010-11 nominal rate |
20.5 |
83.8 |
-31.855 |
-33.008 |
-18.863 |
|
TBL 2010-11 effective rate |
15.8 |
84.1 |
-44.498 |
–20.156 |
-20.654 |
|
Lg 2011-12 effective rate |
15.0 |
85.0 |
-46.650 |
-17.600 |
-20.250 |
|
Lg 2011-12 Bottom10 Eff rt |
12.4 |
80.8 |
-51.644 |
-29.528 |
-39.172 |
|
Lg 2011-12 Top10 Eff rt |
17.5 |
89.5 |
-39.925 |
-4.820 |
-0.745 |
Note: The Lightning’s 2010-11 effective rates were very close to the league’s 2010-11 effective rates of 15.7 and 84.3.
The Lightning’s actual goal differential was -46, so anything above that is an improvement. No team got into the playoffs with a differential below -24 (Florida). In order to get to that minimal level, the Lightning would have needed an effective power play rate higher than 17.5, which was the average effective rate among the top 10 teams in the league (using total PP opportunities, PPGFs, and SHGAs.) At the very top effective rate of 20.0% put up by the Nashville Predators, the Lightning would have a goal differential of -33.2.
In other words, there was too much other stuff contributing to the poor performance for even an elite power play to have made a huge difference in the outcome of the season.
The penalty kill, however, was a different beast, and in most cases, changing the penalty kill alone gave a better goal differential than improving both the power play and the penalty kill. This happened because the Lightning took more penalties than they drew (284 TS vs 269 PPOpps). When I verified the formula by applying it to equal power play and penalty kill opportunities (250 each) the results of improving both were significantly better than the results for improving only one, as common sense would lead us to expect.
What this means is that a smaller improvement in the penalty kill would have had a far greater effect on the outcome of the season than a greater improvement in the power play. A league average penalty kill would have brought the team up above that -24 goal differential, even if the power play remained as bad as it was, and made a significant dent in the hole the team found itself in, both at the game-by-game level or at the level of the season as a whole.
[UPDATE: Jay (Incipient_Senescence) helped me figure out below that there was an error in my spreadsheet. In actuality, improving the PK alone didn’t give better outcomes than improving both. In two cases, however it did give better outcomes than improving the power play alone, which is largely a function of what the PP & PK rates are at the various levels. However, improving both gave better outcomes than just one, as common sense dictates.
The corrected numbers are as follows:
|
Power Play |
Penalty Kill |
GD w this PP |
GD w this PK |
GD w both |
|
|
TBL 2010-11 nominal rate |
20.5 |
83.8 |
-31.855 |
-33.008 |
-18.863 |
|
TBL 2010-11 effective rate |
15.8 |
84.1 |
-32.498 |
-34.156 |
-20.654 |
|
Lg 2011-12 effective rate |
15.0 |
85.0 |
-34.650 |
-31.600 |
-20.250 |
|
Lg 2011-12 Bottom10 Eff rt |
12.4 |
80.8 |
-41.644 |
-43.528 |
–39.172 |
|
Lg 2011-12 Top10 Eff rt |
17.5 |
89.5 |
-27.925 |
-18.820 |
-0.745 |
Still, only the top PP rate made much of a difference, while two of the best PK rates (85% or above) came closer to the -24 that was the lowest goal differential among playoff teams. Improving to within the top-20 in the league in effective special teams rates might have made a real difference in the season.
Side note: one thing that this error of mine showed is that those 12 shorthanded goals made a huge difference. Let’s not keep doing that. ]
