Sample size too small, methodology faulty
There are other variables, which need to be eliminated to ensure that you are only getting results for what you want to test for. Such as the effect of lube, which effect varies when a gun is left standing or otherwise. It's a "springer" in all but power source.
I would - Time start of cocking, cock fast, let it sit for 10 minutes from start of cocking time. Shoot. Do this ideally 10 times, and chrono (yes... I know...)
Repeat above, always 10 minutes from start of cocking, but this time cock slowly, try to make it last 10 seconds just to make it reallll slowwww...
Ideally however... to eliminate other variables such as time of day, air temp, humidity, and more importantly the possibility of repeated shooting changing lube characteristics, etc - alternate a fast and slow cock.
Many thanks in advance for your efforts, let us know tomorrow