Australia - NPL Capital Territory

Visual table

What is the difference between the Points Performance Index and the Performance Rating?

The Points Performance Index (PPI) is based on Points Per Game. Its goal is to mesure the team's capacity to pick up points in the league table. This is a points-centric indicator.

The Performance Rating is based on what we call Performance Points (pPts). Unlike typical Points, where a draw is rewarded at one third of a win, Performance Points are calculated so as to value a draw as half a win.

The typical 3-1-0 point system provides a clear incentive for teams to aim for the win. In the past, the old 2-1-0 system could cause some teams to aim too often for a draw, which could cause some games to become less interesting to watch, especially from a neutral spectator's perspective.

However calculating 'Performance Points' on the base of 1 point for a win, 0.5 point for a draw and 0 point for a defeat allows to take a different look at team performance, as illustrated in the following example:

Let's assume Team A and Team B have each played 10 games.

Team A has the following record: 5 Wins, 0 Draw, 5 Defeats (Total: 15 points | 5 performance points)

Team B has the following record: 2 Wins, 8 Draws, 0 Defeat (Total: 14 points | 6 performance points)

So Team A has been more effective at picking up points than Team B therefore if both teams were to repeat those exact result patterns until the end of the season, Team A will logically finish the season above Team B in the league table.

Now when it comes to analysing performance, one could argue that a team like Team B, that has remained undefeated, winning twice, should not necessarily be considered as having demonstrated a weaker performance than a team that lost half of their matches, as Team A did.

With the classic points system, Team A has a PPG (Points Per Game) of 1.5 and Team B has a lower PPG: 1.4.

With the Performance Points system, Team A has a pPPG (Performance Points Per Game) of 50% and Team B has a higher pPPG: 60%.



How is the Performance Rating calculated?

The Performance Rating (PR) is calculated based on the team's Performance Points Per Game (pPPG) and the pPPG of the opponents already played by the team. It is the average of those two values.

Using the same logic as with the Points Performance Index, the Opponents pPPG value is calculated by taking into account the Away pPPG of opponents played at home and the Home pPPG of opponents played away.