[[Actuarial Notes Wiki|Wiki]] / [[Exam 5 (CAS)]] / **Claim Count Triangle**
## Definition
==Claim Count Triangle== is a development triangle displaying the number of claims (rather than dollar amounts) by accident year and development age, used to analyze claim frequency patterns and development.
## Structure
```
Example Claim Count Triangle:
Development Age (months)
AY 12 24 36 48 60
2020 450 520 545 552 555
2021 475 550 580 590
2022 500 575 610
2023 525 605
2024 550
```
## Uses
### Frequency Analysis
- Track claim reporting patterns
- Identify changes in claim frequency
- Support frequency-severity methods
- Validate loss triangles
### Diagnostic Tool
```
Closed Claim Counts:
- Monitor settlement rates
- Assess claims department efficiency
- Identify changes in closing patterns
Reported Claim Counts:
- Analyze reporting lags
- Detect operational changes
- Project ultimate claim counts
```
### Combined with Loss Triangles
```
Average Severity = Loss Amount / Claim Count
Can develop separately:
- Frequency (claim counts)
- Severity (average per claim)
- Multiply for ultimate losses
```
## Development Patterns
```
Count development factors typically:
- Develop less than loss amounts
- More stable over time
- Lower tail factors
- Mature faster
Example:
12-24 count factor: 1.155
12-24 loss factor: 1.600
(Severity increasing as claims develop)
```
## Related Concepts
- [[Loss Development Triangle#Definition]]
- [[Frequency-Severity Method#Definition]]
- [[Frequency Analysis#Definition]]
## References
- Friedland, Chapter 8