The 9‑I basis is a statutory formula used in many U.S. states to calculate the weekly wage rate for workers' compensation benefits when an employee's earnings are irregular or not easily verified. It takes the employee's total earnings over the preceding nine months, divides by 52 weeks, and applies a predefined index factor to determine the benefit amount.
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How the 9‑I Calculation Works
1. Gather the employee's gross earnings for the nine months before the injury.
2. Add any overtime, bonuses, or commissions earned during that period.
3. Divide the total by 52 to get an average weekly wage.
4. Apply the state‑specific index (often a percentage set by law) to arrive at the final compensation rate.
When the 9‑I Basis Is Applied
It is typically used when regular payroll records are unavailable, such as for seasonal workers, freelancers, or employees with fluctuating income. Courts and claims adjusters rely on the 9‑I basis to ensure a fair, consistent benefit amount.
Impact on Claimants
The resulting weekly benefit may be higher or lower than a standard wage calculation, depending on the employee's earnings pattern. Claimants should provide accurate earnings documentation to avoid underpayment.
Key Considerations
- State laws vary on the exact index factor applied.
- Only earnings within the nine‑month window are considered; earlier income is excluded.
- Employers must retain detailed records to support the calculation if disputed.