It’s normal mg 995 servo

In the 995 datasheet , angular velocity = 0.17s/60 Deg (5 volt)
:= 180 deg = 0.51s But practically I’m getting 805s
And other angles are as follows (irl)
425s = 90deg
805s = 180deg
1130s = 270deg
1475s = 360deg

I want to know why it’s not consistent and (if it’s not a mistake of mine) could I get a formula for the time to degree

Thanks for your time

Really insightful on how to use the laser cutter, especially in projects based application
Thanks Salman