body {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
line-height: 1.6;
color: #333;
max-width: 800px;
margin: 0 auto;
padding: 20px;
}
.mi-wc-calculator-container {
background: #ffffff;
border: 1px solid #e0e0e0;
border-radius: 8px;
padding: 30px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
margin-bottom: 40px;
}
.mi-wc-header {
text-align: center;
margin-bottom: 25px;
color: #003366;
}
.mi-wc-form-group {
margin-bottom: 20px;
}
.mi-wc-label {
display: block;
font-weight: 600;
margin-bottom: 8px;
color: #444;
}
.mi-wc-input {
width: 100%;
padding: 12px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
transition: border-color 0.3s;
}
.mi-wc-input:focus {
border-color: #003366;
outline: none;
}
.mi-wc-helper {
font-size: 12px;
color: #666;
margin-top: 5px;
}
.mi-wc-btn {
display: block;
width: 100%;
padding: 15px;
background-color: #0055aa;
color: white;
border: none;
border-radius: 4px;
font-size: 18px;
font-weight: bold;
cursor: pointer;
transition: background-color 0.3s;
}
.mi-wc-btn:hover {
background-color: #003366;
}
.mi-wc-results {
margin-top: 30px;
background-color: #f8f9fa;
border: 1px solid #e9ecef;
border-radius: 6px;
padding: 20px;
display: none;
}
.mi-wc-result-row {
display: flex;
justify-content: space-between;
margin-bottom: 12px;
border-bottom: 1px solid #e0e0e0;
padding-bottom: 8px;
}
.mi-wc-result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
.mi-wc-result-label {
color: #555;
}
.mi-wc-result-value {
font-weight: bold;
color: #222;
}
.mi-wc-final-premium {
font-size: 24px;
color: #0055aa;
margin-top: 10px;
}
.mi-wc-article {
margin-top: 50px;
}
.mi-wc-article h2 {
color: #003366;
margin-top: 30px;
}
.mi-wc-article h3 {
color: #004488;
margin-top: 25px;
}
.mi-wc-article p {
margin-bottom: 15px;
}
.mi-wc-article ul {
margin-bottom: 15px;
padding-left: 20px;
}
.mi-wc-article li {
margin-bottom: 8px;
}
function calculateMichiganWC() {
// Get input values
var payrollInput = document.getElementById('mi_payroll');
var rateInput = document.getElementById('mi_rate');
var emodInput = document.getElementById('mi_emod');
var discountInput = document.getElementById('mi_discount');
var feesInput = document.getElementById('mi_fees');
// Parse values
var payroll = parseFloat(payrollInput.value);
var rate = parseFloat(rateInput.value);
var emod = parseFloat(emodInput.value);
var discountPercent = parseFloat(discountInput.value);
var fees = parseFloat(feesInput.value);
// Validation
if (isNaN(payroll) || payroll < 0) payroll = 0;
if (isNaN(rate) || rate < 0) rate = 0;
if (isNaN(emod) || emod < 0) emod = 1.0;
if (isNaN(discountPercent) || discountPercent < 0) discountPercent = 0;
if (isNaN(fees) || fees < 0) fees = 0;
// 1. Calculate Manual Premium = (Payroll / 100) * Rate
var manualPremium = (payroll / 100) * rate;
// 2. Calculate Modified Premium = Manual Premium * E-Mod
var modifiedPremium = manualPremium * emod;
// 3. Calculate Discount Amount
var discountAmount = modifiedPremium * (discountPercent / 100);
// 4. Calculate Standard Premium
var standardPremium = modifiedPremium – discountAmount;
// 5. Final Estimated Premium = Standard Premium + Fees
var finalPremium = standardPremium + fees;
// Display Results
document.getElementById('res_manual').textContent = formatMoney(manualPremium);
document.getElementById('res_modified').textContent = formatMoney(modifiedPremium);
document.getElementById('res_discount').textContent = "-" + formatMoney(discountAmount);
document.getElementById('res_final').textContent = formatMoney(finalPremium);
// Show result container
document.getElementById('mi_results').style.display = 'block';
}
function formatMoney(amount) {
return '$' + amount.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
}
How Michigan Workers Compensation Rates Are Calculated
Calculating workers' compensation premiums in Michigan involves a specific formula that accounts for the size of your workforce, the risk level of your industry, and your company's safety history. Michigan operates under an "open competition" system, meaning insurance carriers can file their own rates based on advisory pure premiums, leading to price variations between insurers.
1. The Basic Formula
The foundation of your premium is the Manual Premium calculation. This is determined by dividing your total annual payroll by 100 and multiplying it by the specific class code rate assigned to your business activities.
Formula: (Payroll / 100) x Class Code Rate = Manual Premium
For example, if you run a plumbing business (Class Code 5183) with a payroll of $200,000 and a rate of $2.50, your manual premium would be $5,000.
2. Class Codes and Base Rates
In Michigan, businesses are classified using codes maintained by the National Council on Compensation Insurance (NCCI) or specific state bureaus. Each 4-digit code represents a specific type of work (e.g., Clerical Office Employees, Carpentry, Trucking). Higher-risk professions generally have higher base rates per $100 of payroll compared to low-risk clerical roles.
3. The Experience Modification Factor (E-Mod)
The E-Mod adjusts your premium based on your specific claims history compared to the average for your industry. It serves as a multiplier in the calculation:
- 1.0 E-Mod: Average safety record (no impact on premium).
- Below 1.0 (Credit Mod): Better than average safety record (reduces premium).
- Above 1.0 (Debit Mod): Worse than average safety record (increases premium).
New businesses usually start with an E-Mod of 1.00 until they have sufficient history (typically 3 years) to generate a rating.
4. Discounts and Expense Constants
After the E-Mod is applied, other factors come into play:
- Premium Discounts: Insurers often provide discounts for larger policies because the administrative cost relative to the premium is lower.
- Expense Constant: A flat charge (often around $200-$250) covers the administrative cost of issuing and maintaining the policy.
- State Assessments: Michigan may levy specific assessments, such as the Redemption Fee or contributions to the Second Injury Fund, which are added to the final cost.
Why Your Rate Might Vary
Because Michigan is an open competition state, insurance carriers have the flexibility to file different rates for the same class code. It is highly recommended to shop around or work with an independent agent who can compare quotes from multiple carriers to ensure you are receiving the most competitive rate for your specific class code and E-Mod.