Help with AeT assessment

Longtime lurker, first time poster here.

I’m hoping for some AeT assessment advice from others who have more experience looking at the results.

http://tpks.ws/BEKFIDW5LOJJHG5BU4HNRYLGXM

I performed the test on a treadmill with a low grade, and ramped up the speed for the first 10 minutes, after which I left it on 5.8mph for the remainder of the test. My garmin estimated pacing for the activity so you can ignore that. It appears as if it takes until around the 20min mark for my heartrate to stabilize around low 140s. Using the 20min mark as the start of the test I get 143bpm as my avg for the first half and 146 as my average for the second half, which gives me a drift of ~2%. I’m guessing I should retake at slightly faster pace (5.9 – 6 mph) to see if that gets me the 3.5 – 5% drift range.

Here are my questions:

1) Would the starting heartrate for this test be 140? or 143? There is a fair amount of variation in the first couple minutes of the test.

2) Should I account for the fact that the test was only 50 minutes in the amount of drift I calculate? For ex, multiplying 2% by a factor of 60/50 to normalize to an hour = 2.4% drift

I’m sure I’m really splitting hairs here, but I tend to be a little ocd about some things.

-Patrick