[[Actuarial Notes Wiki|Wiki]] / [[Exam 5 (CAS)]] / **Actual vs Expected Analysis**
## Definition
==Actual vs Expected Analysis== is a diagnostic technique comparing actual loss emergence to expected patterns to identify reserve strengthening/weakening and development trends.
## Methodology
```
A/E Ratio = Actual Incurred / Expected Incurred
Calculation:
Expected = Prior Ultimate Estimate
Actual = Current Incurred
A/E > 1.0: Adverse development
A/E < 1.0: Favorable development
A/E = 1.0: As expected
```
## Uses
- Monitor reserve adequacy
- Identify development trends
- Validate methods
- Track actual vs projected
## Example
```
AY 2022 @ 12/31/2023:
Prior estimate (12/31/2022): $1,000,000
Current incurred (12/31/2023): $1,050,000
A/E = $1,050,000 / $1,000,000 = 1.05 or 105%
5% adverse development
```
## Related Concepts
- [[Reserve Adequacy#Definition]]
- [[Roll Forward Analysis#Definition]]
## References
- Friedland, Chapter 11