Your PI is made up of your top 5 results which are given a time weighted coefficient, therefore it is not always possible to determine from your scores which results are used for the General PI calculation. For example, a new PI score of 500 can be used in place of an older score of 505.
Please be assured that the calculation will always give you the best possible score looking at all your results and that we apply the same exact calculation to every athlete in our database.
Method of calculation
Overall Goal:
The process gives more importance to recent and better performances and adjusts for the runner’s racing experience.
Step-by-Step Process
Step 1: Collect Valid Race Scores
Gather all race scores from the past 36 months.
Select the top 5 best ITRA score performances
Ignore any races where:
The runner Did Not Finish (DNF).
The score is 0.
Step 2: Apply Time Weighting
Assign a weight to each score based on how long ago the race took place:
Race Age (Months Ago) | Time Weight |
|---|---|
0–11 months | 1.000 |
12–17 months | 0.995 |
18–23 months | 0.990 |
24–29 months | 0.985 |
30–35 months | 0.980 |
Multiply each race score by its corresponding time weight.
Step 3: Rank the Scores
Sort the time-weighted scores from highest to lowest.
Assign each result a rank based on its position in the list:
Rank 1 = Best score, Rank 2 = 2nd best, ..., up to Rank 5.
Step 4: Apply Experience Weighting
Simulate different scenarios assuming the runner had:
1 result in the last 36 months
2 results in the last 36 months
3 results in the last 36 months
4 results in the last 36 months
5 results in the last 36 months
For each simulation, apply experience weights to the top scores:
# of Races Used | Score Weights Applied |
|---|---|
1 | 1st = 0.97 |
2 | 1st = 0.99, 2nd = 0.98 |
3 | 1st = 1.00, 2nd = 0.99, 3rd = 0.99 |
4 | 1st = 1.01, 2nd = 1.00, 3rd = 1.00, 4th = 0.99 |
5 | 1st = 1.02, 2nd = 1.01, 3rd = 1.00, 4th = 1.00, 5th = 0.99 |
For each scenario, calculate the weighted average of the top scores using these experience weights.
Step 5: Select Best Simulation
Out of the 5 simulations (1 to 5 top scores), choose the one that gives the highest overall PI.
This PI becomes the runner’s final ITRA Performance Index level
Note on Distance Categories
Repeat the entire process separately for each Distance Category (e.g., 5K, 10K, Marathon).
In Step 1, only include races that belong to the relevant distance category.
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