School Retention Rate Calculator Formula
Understand the math behind the school retention rate calculator. Each variable explained with a worked example.
Formulas Used
Retention Rate
retention_rate = returning_students / eligible_to_return * 100Students Lost to Attrition
attrition_count = eligible_to_return - returning_studentsAttrition Rate
attrition_rate = (1 - returning_students / eligible_to_return) * 100Variables
| Variable | Description | Default |
|---|---|---|
start_enrollment | Start of Year Enrollment | 500 |
returning_students | Returning Students Next Year | 460 |
graduates | Graduates (expected departure) | 25 |
eligible_to_return | Derived value= start_enrollment - graduates | calculated |
How It Works
How School Retention Rate is Calculated
Retention rate measures the proportion of non-graduating students who return the following year.
Formula
Retention Rate = Returning Students / (Start Enrollment - Graduates) x 100
Attrition Rate = 1 - Retention Rate
High retention (above 90%) indicates student and family satisfaction. Attrition drives enrollment decline and budget instability.
Worked Example
500 students at start, 25 graduates, 460 return next year.
- 01Eligible to return: 500 - 25 = 475
- 02Retention rate: 460 / 475 x 100 = 96.8%
- 03Attrition: 475 - 460 = 15 students lost
- 04Attrition rate: 3.2%
Frequently Asked Questions
What is a good retention rate?
Above 95% is excellent for K-12. For colleges, 80-90% freshman-to-sophomore retention is strong.
How do I improve retention?
Focus on student engagement, parent communication, academic support, school climate, and addressing individual concerns promptly.
Should transfers be counted separately?
Ideally yes. Track voluntary departures separately from relocations to understand controllable attrition.
Ready to run the numbers?
Open School Retention Rate Calculator