Rather than gradually work my way back in time, I thought it best to just jump straight back to the first possible year to calculate PDO: 1983-84.

It was a different time.  The season began with Bonnie Tyler’s “Total Eclipse of the Heart” at the top of the charts, soon to be knocked off by “Islands in the Stream”.  Martin Luther King Day was officially declared a national holiday.  Able Archer 83 unknowingly brought the Soviets and Americans to the brink of WWIII.  And the NHL finally began tracking shots against, allowing for retroactive PDO.

In the write-up I did on PDO in the first place, I noted that:

• An all-situations PDO higher than 100.9% very strongly correlates to a playoff appearance
• A PDO below 99.2% very strongly correlates to missing the playoffs
• PDO has little predictive value in the playoffs, although I pointed out that further research would be needed.

The following table shows each team’s all situation PDO in 1983-84.  The key numbers are on the right: “PDO” is the original number I had without taking the empty net goals into account, and “AdjPDO” is the big number that has everything properly balanced and comes out to a leaguewide total of 100.0000000000.  SV% is the total number of goals against from number of shots against; TmSV% includes the empty net shots (which had to be adjusted for).  In this table, AdjPDO is simply S% plus TmSV%.

Team	GF	S	GA	SA	EN	S%	SV%	TmSV%	PDO	AdjPDO
Edmonton	446	2613	314	2638	4	17.069	0.881	0.881	105.166	105.184
NY Islanders	357	2423	269	2669	1	14.734	0.899	0.899	104.655	104.659
Quebec	360	2286	278	2249	2	15.748	0.876	0.876	103.387	103.398
Boston	336	2398	261	2091	3	14.012	0.875	0.875	101.530	101.547
Buffalo	315	2388	257	2146	2	13.191	0.880	0.880	101.215	101.226
Washington	308	2534	226	1961	4	12.155	0.885	0.885	100.630	100.653
Minnesota	345	2536	344	2605	5	13.604	0.868	0.868	100.399	100.424
NY Rangers	314	2552	304	2505	9	12.304	0.879	0.879	100.168	100.212
Calgary	311	2565	314	2625	3	12.125	0.880	0.881	100.163	100.177
Toronto	303	2344	387	2826	6	12.927	0.863	0.863	99.232	99.261
Philadelphia	350	2945	290	2287	5	11.885	0.873	0.873	99.204	99.232
Hartford	288	2402	320	2482	5	11.990	0.871	0.871	99.097	99.123
Chicago	277	2459	311	2519	7	11.265	0.877	0.877	98.919	98.953
St. Louis	293	2427	316	2392	8	12.072	0.868	0.868	98.862	98.906
Winnipeg	340	2584	374	2619	2	13.158	0.857	0.857	98.878	98.889
Detroit	298	2326	323	2300	14	12.812	0.860	0.860	98.768	98.853
Vancouver	306	2494	328	2338	12	12.269	0.860	0.860	98.240	98.312
Montreal	286	2293	295	2051	4	12.473	0.856	0.856	98.090	98.118
Pittsburgh	254	2267	390	2896	12	11.204	0.865	0.866	97.737	97.793
Los Angeles	309	2467	376	2524	11	12.525	0.851	0.852	97.628	97.693
New Jersey	231	2101	350	2554	5	10.995	0.863	0.863	97.291	97.318

The first thing to note is that there are only six teams inside the 99.2%-to-100.9% range at all.  I believe this to be a symptom of a significantly unbalanced league, one which saw just five teams finish within 10% of .500.  There were also five 100-point teams, meaning that in a 21-team league there were as many teams that finished with 100+ points as finished anywhere between 72-88.

In the Campbell Conference, exactly three out of ten teams finished above .500: Calgary at 34-32-12, Minnesota at 39-31-10, and Edmonton at 57-18-5.  Both Minnesota and Calgary would have missed the playoffs if they had been in the Patrick Division, and either one would have been the #4 seed in the Adams.

However, we must still see if PDO had any predictive value at this time despite the divisional playoff system and the unbalanced league.

In the first round:

• Montreal (lower) defeated Boston (higher)
• Quebec (higher) defeated Buffalo (lower)
• NY Islanders (higher) defeated NY Rangers (lower)
• Washington (higher) defeated Philadelphia (lower)
• Calgary (higher) defeated Vancouver (lower)
• Edmonton (higher) defeated Winnipeg (lower)
• St. Louis (higher) defeated Detroit (lower)
• Minnesota (higher) defeated Chicago (lower)

That’s 7-1 in the first round for the higher PDO team.  And of these, despite the lack of overall competitive balance, only two series involved a massive disparity in team points that season: Edmonton finished 46 points ahead of Winnipeg and swept them, and Boston finished 29 points ahead of Montreal but were themselves swept.

In the second round:

• NY Islanders (higher) defeated Washington (lower)
• Montreal (lower) defeated Quebec (higher); this was the series that featured the infamous Good Friday Massacre
• Edmonton (higher) defeated Calgary (lower)
• Minnesota (higher) defeated St. Louis (lower)

That’s another 3-1 for the higher team.

And the rest of the way:

• Edmonton (higher) defeated Minnesota (lower)
• NY Islanders (higher) defeated Montreal (lower)
• Edmonton (higher) defeated NY Islanders (lower)

All in all, that’s a shocking 13-2 overall record for the higher PDO team in each playoff series.