[nfotiu]

Originally Posted by Enoch Root

Are you sure about that?

My understanding is that it starts as 1, then if you score, a 2nd one starts, and if you score again, a 3rd, etc.

So if you don't score in the 5 minutes, you go 0 for 1. If you score once, you go 1 for 2, if you score twice, 2 for 3, and so on.

It looks like you are right.

Power-Play Goal
A goal scored by a Club while it has a manpower advantage due to an opponent's penalty. Following are some examples of what is and is not considered a power-play goal:
if a Club has an advantage on a minor penalty starting at 2:02 of the period and it scores at 4:02, the goal is not a power-play goal.
if a Club scores on a delayed penalty, the goal is not a power-play goal.
if a Club has an advantage due to a five-minute major or match penalty, that Club is always credited with having one more advantage than the number of power-play goals it scores during that advantage, because the penalty does not expire. A new advantage begins after each power-play goal. For example, if Team A scores three goals during a major penalty, it is credited with four advantages.
if a Club is on a power-play for any length of time, it is considered to have had an advantage.
if a minor penalty is incurred by a Club on a power-play due to a major penalty, a new advantage is given to that Club when its minor penalty expires, provided the opponent's major penalty is still in effect.

http://www.nhl.com/ice/page.htm?id=26374

I wonder if it changed somewhere along the way. I felt pretty sure they were counted as 2 PPs at some point.