My google fu is weak.
In Golden Cheetah if I go to Trends > Summary and look at the Athlete Bests I see 30 Sec peak power, 1 min peak power, etc. In each of those sections I see the position number, wattage, date and a number in parenthesis. What is that number telling me and why is it something negative and other times positive?
20 min Peak Power
- 258 7 Apr 2019 (-2)
- 242 10 Aug 2019 (-7)
- 242 8 Aug 2019 (-9)
- 238 23 Apr 2019 (10)
- 236 21 Apr 2019 (13)
- 235 21 Mar 2019 (-5)
- 233 28 Aug 2019 (-6)
- 233 11 Oct 2019 (9)
- 233 13 Aug 2019 (-8)
- 232 17 Oct 2019 (-3)
That’s telling you what your TSB (Training Stress Balance) was at the time you set the PR. This could be useful or not, depending on a bunch of factors (e.g., the type of training you’ve been doing, overall training volume, your individual genetics, etc…)
Random number example follows: Some people need/like to be +20 come race day in order to perform their best. While some will feel stale at +20 and prefer -10. Again, it is very individual.
Use it for trending against how you feel on those days (RPE) and how you actually perform to see what works best for you.
Edit addition: Found a relevant TR write-up for you:
Thank you for asking, I was wondering about the same for ages