Perform CHOP fps explanation

I noticed the FPS and Frame Time shown in the Perform CHOP change constantly, even though it remains “realtime” and the dropped frame count is always zero. Here’s a picture of a trail CHOP showing it jump between 24.0 and 25.0, while my cook rate is set to 23.98. I’m trying to understand what this all means. I thought the FPS should always stay at exactly the chosen cook rate as long as the CPU can keep up. My CPU usage is minimal on this simple test.

Meanwhile, the FPS indicator in the toolbar remains constant at 23.98. Is there an expression to get that number?

The FPS is calculated via (1000.0 / ‘time it took to calculate the frame’). So this can result in some roundoff errors. If the dropped_frames number is staying at 0 then you aren’t dropping any frames. That’s the key channel to look at.
The FPS indicator in the toolbar isn’t going to change since that’s the target FPS.