The 90th percentile response time of the Transaction Controller is varying across individual API calls.

### Expected behavior

I'm executed a JMeter script with 3 threads and 10 iterations on the Application Launch Page. During the test, we observed that the response times for individual API calls were in milliseconds, while the response times for the Transaction Controller were around 15 seconds.

This behavior was consistent across multiple executions.

I've attached a file for your reference. The Launch Page includes 4 API calls.

Number of iterations is 30
Number of API calls: 4
In total, 120 request responses are provided in the attached file for your review and Transaction controller response time also provided.

Please advise on how the 90th percentile response times for the Transaction Controller are being calculated.

[90Percentile.xlsx](https://github.com/user-attachments/files/17327204/90Percentile.xlsx)

### Actual behavior

_No response_

### Steps to reproduce the problem

Add multiple API calls within one Transaction Controller and ensure that "Generate Parent Sample" is unchecked. Afterward, execute the script 25 or 30 times and verify if the 90th percentile response time for the Transaction Controller matches the 90th percentile response times of the individual API calls.

### JMeter Version

5.6.3

### Java Version

1.8.0_181

### OS Version

Microsoft Windows 10