Official NHA Assessment
Race 4: ZAMBEZI DRIFT BORROWDALE B STAKES 84 (For All Horses with a nett rating of 84 & below)
Line Horse
Jacky Sparrow
Reference for assessment
Exact Matches
0 / 5
Calculated = Official
Close Matches
1 / 5
Within 2 points
Significant Diffs
4 / 5
More than 5 points
Detailed Assessment
------------------------------------------------------------------------------------------------------------------------ Pos Horse Age Weight Fin Lengths WFA Pre Race Rating New Adj ------------------------------------------------------------------------------------------------------------------------ 1 Jacky Sparrow 3 57.5 1 0.00 1.5 78 78 78 +0 2 Kallipos 3 57.0 2 0.05 1.5 72 77 77 +5 3 Battle Of Seattle 2 60.0 3 4.05 0.5 77 85 85 +8 4 Forgotten Time 3 60.0 4 4.15 1.5 76 83 83 +7 99 Red Top 5 57.0 99 0.00 0.0 - 80 80 +0 ------------------------------------------------------------------------------------------------------------------------
Horse-by-Horse Comparison
| Pos | Horse | Pre-Rating | Official New | Calculated | Discrepancy | WFA (kg) | Line Horse | Calculation |
|---|---|---|---|---|---|---|---|---|
| 1 | Jacky Sparrow Line | 78 | 80 | 78 | +2 | 1.5 | ||
| 2 | Kallipos | 72 | 63 | 77 | -14 | 1.5 | - | |
| 3 | Battle Of Seattle | 77 | 59 | 85 | -26 | 0.5 | - | |
| 4 | Forgotten Time | 76 | 76 | 83 | -7 | 1.5 | - | |
| 99 | Red Top | - | 70 | 80 | -10 | 0.0 | - |
Assessment Methodology
Calculation Steps:
- Identify Line Horse - consistent performer used as reference
- Calculate WFA Allowance based on age, distance, and month
- Apply Drag Adjustment for beaten margin
- Calculate Actual Weight Performance:
Weight - Drag - WFA - Compare to Line Horse to determine race rating
- Apply special rules (maiden caps, layoff allowance)
Key Formulas:
- Drag Effect: Varies by distance (see Benchmarks page)
- 1 length ≈ 1kg at 1 mile (1600m)
- WFA Scale: Based on Admiral Rous's 1855 table
- Rating Points: 1kg = 2 rating points