Total employees who left (voluntary + involuntary) during the month.
Average Headcount:0
Monthly Attrition Rate:0.00%
Projected Annual Rate:0.00%
function calculateAttrition() {
// Get input values
var startCount = document.getElementById('startCount').value;
var endCount = document.getElementById('endCount').value;
var separations = document.getElementById('separations').value;
// Validation
if (startCount === "" || endCount === "" || separations === "") {
alert("Please fill in all fields to calculate the rate.");
return;
}
var start = parseFloat(startCount);
var end = parseFloat(endCount);
var sep = parseFloat(separations);
if (start < 0 || end < 0 || sep < 0) {
alert("Values cannot be negative.");
return;
}
// Calculate Average Headcount
// Formula: (Start + End) / 2
var average = (start + end) / 2;
if (average === 0) {
alert("Average headcount cannot be zero.");
return;
}
// Calculate Monthly Attrition Rate
// Formula: (Separations / Average Headcount) * 100
var monthlyRate = (sep / average) * 100;
// Calculate Annualized Rate
// Formula: Monthly Rate * 12 (Linear projection)
var annualRate = monthlyRate * 12;
// Update DOM
document.getElementById('avgHeadcount').innerHTML = average.toLocaleString(undefined, {minimumFractionDigits: 1, maximumFractionDigits: 1});
document.getElementById('monthlyRate').innerHTML = monthlyRate.toFixed(2) + "%";
document.getElementById('annualRate').innerHTML = annualRate.toFixed(2) + "%";
// Show result box
document.getElementById('result').style.display = 'block';
}
Understanding Monthly Attrition Rate
The monthly attrition rate is a critical Human Resources metric that measures the rate at which employees leave a workforce over a single month. It includes both voluntary exits (resignations, retirement) and involuntary exits (terminations). Tracking this metric monthly allows organizations to identify trends, spot issues with retention early, and measure the effectiveness of employee engagement strategies.
The Formula
To calculate the monthly attrition rate accurately, standard HR practice uses the average headcount for the month as the denominator to account for fluctuations in staffing levels.
Attrition Rate = (Separations / Average Headcount) × 100
Where:
Separations: The total number of employees who left the company during the month.
Average Headcount: (Headcount at Start of Month + Headcount at End of Month) / 2.
Calculation Example
Let's say a software company wants to calculate their attrition for June:
Employees on June 1st: 200
Employees on June 30th: 210 (implies net growth despite exits)
This means 2.44% of the workforce left during the month of June.
Annualized Attrition
While the monthly rate tells you what happened in the last 30 days, businesses often look at the Annualized Attrition Rate to compare against industry benchmarks. This is a projection assuming the current month's turnover behavior continues for a full year.
Formula: Monthly Rate × 12
In our example: 2.44% × 12 = 29.28%. This high figure suggests that if the trend continues, the company will lose nearly 30% of its staff by year's end, signaling a need for retention intervention.
What is a "Good" Attrition Rate?
Attrition rates vary heavily by industry. Retail and hospitality often see monthly rates of 3-5% (annualized 30-60%), while finance or technology sectors may aim for monthly rates below 1% (annualized 10-12%). Consistently high monthly attrition can lead to increased recruitment costs, loss of institutional knowledge, and decreased morale.