Another leak question

I use straight cpap. Pressure set at 7. Swift Fx nasal pillow chart says the vent rate should be about 27-28 l/min. Is the vent rate the flow through the vent holes and so the minimum total leaks should be the same as the expected vent rate? But my sleepyhead data shows my minimum total leaks varies from as low as 17 to as high as 24 (l/min). How can my minimum total leaks be less than the expected vent rate and what causes it to vary? Am I blocking the vent holes? Would the twists and turns in the hose slow down the flow?

The vent rates also have a standard plus or minus deviation in the fine print.
Don't worry about the total leak seeming less than the stated vent rate. I had this happen even with my Encore software.
It continually gave me a pretty much straight line at 28 L/min and my vent rate is close to 35 L/min at my average pressure.
I doubt you are blocking the vent holes.