NHL Average Age between 1917/18 - 2009/10

Average age of NHL players (How was this calculated?) has gone through many fluctuations over the years. Here I concentrate particularly on the age difference between forwards, defensemen and goalies as well as the average age difference between regular season and playoffs.

The same data is shown twice in two different chart sets to facilitate comparison. The first set of charts compares players by position for regular season and playoffs separately. The second set concentrates on the difference in average age between regular season and playoffs across player positions. Click on the buttons above the charts to switch between charts. Data for the charts is available on a separate page.

The charts below show the average age of forwards, defensemen and goalies for all seasons between 1917/18 - 2008/09. Results show that during most seasons, forwards have had the lowest average age and the goalies the highest. Results are consistent across regular and playoff seasons.

The next charts show the average age separately for forwards, defensemen and goalies. Each chart displays the average age during regular season and playoffs.

There are two things to note. First, for all position groups the average age is usually higher in playoffs that it is during the regular season. Thus, it appears that more experienced teams make it to the playoffs more often than the inexperienced teams.

Second, as one would expect, the weighted average age is higher than the simple average, because more experienced players play more games during the season than the younger players who are only beginning their careers.

NHL Numbers (2009-10 Season): NHL Average Age by Team

NHL Numbers (2009-10 Season): NHL Average Age by Player Nationality

Average age is calculated using two different methodologies. The first is a straight forward arithmetic average, where each player has the same weight in the data set. In the charts above, this methodology is identified by SA (Simple Average). The second methodology takes into account the number of games that player has played during the season. The age of each player is weighted by the number of games he has played. This methodolgy is identified by WA (Weighted Average).

To calculate the simple average, the age of each player during any particular season is first determined by calculating the number of days between the player birth date and the December 31st of the season in question. This difference (age of the player measured in days) is then summed for each season and divided by the number of players during that season. Finally, the average is divided by 365 to convert it into years.

The weighted average is calculated similarly, except that the age of each player is weighted by the number of games he has played during the season. The weighted average thus considers the impact that the player has had during the season.

A small number of players have been excluded from the data set, because their birth dates are unknown.