NHL Career Charting: The Pre-BTN Era and What We Can Still Do With Historical Data


Photo by “IrisKawling”, via Wikimedia Commons

Hockey statistics have always been fairly historically limited; most of the so-called “fancy stats” have only been tracked (and easily track-able league-wide) back through the 2007-08 season. The prior years have a veil of fog over them, though there is fairly decent shot data going all the way back to the 1952-53 season (thanks to the Hockey Summary Project; I’ve been able to bring the data together), good game-by-game individual player data going back to 1987-88 (thanks to Hockey Reference via Dan Diamond & Associates), and gradually-improving TOI data going back to 1997-98 (thanks to NHL.com and Hockey Reference). Unfortunately, this has lead to a relative dearth of research into the years of the “Pre-BTN” Era, so-called because 2007-08 was the first year we received in-depth, league-wide data from Gabe Desjardins’ Behind the Net stats site and Vic Ferrari’s timeonice.com.

Having a background in history, and also having grown up as a fan of the league in this grey statistical era, I have spent the last couple years trying to compile and present statistics from the Pre-BTN Era in ways that can help provide a window into those years (and possibly inform our understanding of the present-day game). I’m somewhat indebted to Iain Fyffe, a guy who’s been doing similar yeoman’s work much longer than myself at Hockey Prospectus, though more recently he’s been sharing his work at his own site, Hockey Historysis.

The fact of the matter is that there is actually an enormous amount of information out there, and more importantly with graph work we can really do some interesting things. First case in-point is what I call “career charting;” essentially, charting a player’s shots in a game relative to their team’s shots in those same games. Using the metric %TSh, or percentage of team shots, this provides an interesting glimpse into player contributions, workload, and development in the Pre-BTN Era. Adding some artistic (and informational flourish), I present to you Pierre Turgeon:


For this measure, I used a rolling 25-game average, primarily because by these charts we can see that %TSh settles down pretty substantially by 25 games or so. I love this chart in particular because, for one, it shows us a pretty nice aging curve of a player who was undeniably receiving regular forward minutes, and for two it shows us the impact of switching teams. For point of reference, 8% is typically the mark for a top-6 forward, unless they’re an extreme 2nd-line assist man. Turgeon was never a sniper, but as you can see here he was a top-6 forward for 13 seasons (and, away from these stats, a very good two-way forward). Incidentally, he was also ridiculously photogenic.

Not satisfied at just Pierre Turgeon, I wanted to take a couple more forwards to see how their career arcs looked. To avoid wrangling with guys that might’ve suffered from low TOI, I took a couple more familiar faces:



Once again, you can see team changes at work here. Just as interesting, these are three very good (two HOF) players, all of whom were traded at young ages and prior to their best seasons. Hull, infamously, was traded to the Blues for past-their-primes Rob Ramage and Rick Wamsley, while Turgeon was traded for a package including Pat LaFontaine and Shanahan essentially traded for Scott Stevens.

To add some nuance, I wanted to bring another player into the fold, a guy who maybe wasn’t ever considered a top player but nevertheless a worthy NHLer. Since I wanted to reach back to a similar era as the above three forwards, Adam Graves seemed like a good option:


Once again, we’re seeing the similarities between Graves and the other forwards in regards to aging curves, the effect of trades, and even the specter of teams giving up on young talent before their prime. Graves was traded away from Detroit as part of a deal for failed Gretzky-successor Jimmy Carson (he of the historic Gretzky trade to Los Angeles), Graves scored an incredible 52 goals in 1993-94 during the Rangers’ Cup run, cementing his place in the hearts of New York fans. That was his peak, though as you can see above he was a major player in the Rangers offense for years afterward.

Really, this is just the beginning of what I can do with this data and %TSh. Let’s say, for instance, that you want to present these charts together and compare these forwards’ progression as they increased their NHL experience:

You can also take the players and match their age for each individual game to their %TSh, and bring them in line with each other. Establish their average, perhaps:


The late spike is, without a doubt, “survivorship bias,” as both Graves and Turgeon drop out of the equation yet Hull and Shanahan forge ahead. Whatever the case, you can definitely see a trend there. Once again, we can compare individual players to their counterparts:

As we can see, Hull is an example of extreme peak with ample perseverance; it sometimes gets lost in his career narrative that he didn’t get a regular NHL job until he was 23. Shanahan was granted early entry, and his perseverance was even more remarkable because he played a more-physical game. Turgeon lacked the shooter prowess of the previous two, and Graves was simply a good NHLer. These Career Charts go a long ways towards depicting that, and also giving us grounds for comparison and the complexity of player evolution, trades, and even injury (which I didn’t take the time to show, but could in the future).

Obviously, there are limitations here. For one, using shots can disadvantage players that do not shoot the puck; for that reason, I’m considering including finer metrics, including assists per team assists, game-by-game, as well as separating forwards and defenseman and presenting these as percentage of team forward shots and team defensemen shots. There’s also the matter of tying these to shots, which does bring us closer to players that have more/less ice time, but still could disadvantage primarily defensive players. Their value if they can’t generate any shots whatsoever is debatable, but nevertheless they won’t show up particularly well here. Whatever the case, Career Charting demonstrates that, despite the dearth of fancy stats in the Pre-BTN Era, there is a lot of information out there and a lot of ways we can make historical research interesting and helpful.

4 thoughts on “NHL Career Charting: The Pre-BTN Era and What We Can Still Do With Historical Data

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s