California Whole Person Impairment (WPI) Calculator
Calculated Ratings
Combined Whole Person Impairment (WPI):0%
Standard Adjusted Rating (DFEC 1.4):0%
Age-Adjusted Rating:0%
Final Estimated Permanent Disability: 0%
Understanding California WPI and PD Ratings
In California workers' compensation cases, the Whole Person Impairment (WPI) is the foundational number used to determine your Permanent Disability (PD) rating. Unlike simple addition, California uses the Combined Values Chart (CVC) to merge multiple impairments, ensuring a person cannot exceed 100% total disability.
How the Calculation Works
The Combination Formula: Multiple impairments are combined using the formula A + B(1 - A). This means if you have two 10% impairments, they combine to 19%, not 20%.
DFEC Adjustment: For most injuries after 2013, the combined WPI is multiplied by a factor of 1.4 to account for Diminished Future Earning Capacity.
Age Adjustment: The rating is adjusted based on your age at the time of injury. Younger workers (below 39) generally receive a slight decrease, while older workers receive an increase, reflecting the difficulty of returning to the workforce.
Example Scenario
If a 50-year-old worker has a 10% WPI for a back injury and a 5% WPI for a leg injury:
Combined WPI: 15% (rounded using CVC math).
Standard Rating: 15% x 1.4 = 21%.
Age Adjustment: Being 50 (older than the 39-year-old baseline) adds roughly 2% points.
Final PD: Approximately 23%.
Note: This calculator provides an estimate based on standard 2013-2024 PDRS guidelines. It does not include Occupational Group adjustments, which require specific job titles.
function calculateRating() {
var wpi1 = parseFloat(document.getElementById('wpi_val1').value) || 0;
var wpi2 = parseFloat(document.getElementById('wpi_val2').value) || 0;
var wpi3 = parseFloat(document.getElementById('wpi_val3').value) || 0;
var age = parseInt(document.getElementById('inj_age').value) || 39;
// Sort descending for CVC logic
var values = [wpi1, wpi2, wpi3].sort(function(a, b){ return b – a; });
// Combination Logic: A + B(1 – A)
var currentCombined = values[0] / 100;
for (var i = 1; i < values.length; i++) {
var nextVal = values[i] / 100;
currentCombined = currentCombined + (nextVal * (1 – currentCombined));
}
var combinedWpiPercent = Math.round(currentCombined * 100);
// Step 2: DFEC Multiplier (Standard California factor 1.4)
var dfecAdjusted = Math.round(combinedWpiPercent * 1.4);
// Step 3: Age Adjustment (Approximate Calculation)
// Baseline age is 39. Adjustments are roughly 0.1 to 0.2 points per year group
var ageDiff = age – 39;
var ageAdjustment = 0;
if (ageDiff !== 0) {
// Simplified lookup logic for age adjustment
// In actual PDRS tables, this varies by rating level, but 0.15 is a standard average shift
ageAdjustment = Math.round(ageDiff * 0.12);
}
var finalPd = dfecAdjusted + ageAdjustment;
// Bounds check
if (finalPd 100) finalPd = 100;
// Display Results
document.getElementById('out_combined_wpi').innerText = combinedWpiPercent;
document.getElementById('out_dfec').innerText = dfecAdjusted;
document.getElementById('out_age_adj').innerText = (dfecAdjusted + ageAdjustment);
document.getElementById('out_final_pd').innerText = finalPd;
document.getElementById('rating-results').style.display = 'block';
}