When standings go up or down they do so as a percentage; this is always a percentage decay towards the extreme end of the scale. For example, if someone has 1.0 standing with an NPC corporation and completes a mission that changes standing by +5%, then the current standing is increased by 5% of the difference from 1 to 10; that’s a change of +0.45 with an end result of 1.45. However, if someone else with a 4.0 standing completes the same mission under the same circumstances and also gets a 5% increase, then that’s 5% of the difference from 4 to 10; that’s a change of +0.30 with an end result of 4.30.
If something causes a standing decrease, then it’s a percentage decay towards −10. For example, if someone with 1.0 standing suffers a −5% change, then that’s 5% of the difference from 1 to −10; that’s a change of −0.55 with an end result of 0.45. If someone with 4.0 standing suffers that same −5% change, then it’s 5% of the difference from 4 to −10; that’s a change of −0.7 with an end result of 3.3.
The formula for standing increase is
New standing=Old standing+(10−Old standing)×Standing increase
The formula for standing decrease is almost same, just towards -10
New standing=Old standing+(−10−Old standing)×Standing decrease
where Standing decrease is the decimal form of standing change. For example 0.4% would be 0.004.
The consequence of this math is that the higher your standings are, the less effective standings increases become and the more dramatic penalties become. For example a standing loss of 1% turns 9.0 standing into 8.81 but increase of 1% would bring 9.0 standing to 9.01.
The equation for resulting standing for receiving same standing gain multiple times is
Sn=S0×(1−Standing increase)+10×(1−(1−Standing increase)n)
And in similar style the equation for resulting standing for receiving same standing loss multiple times is
Sn=S0×(1−Standing decrease)−10×(1−(1−Standing decrease)n)
if you want further explanation, feel free to reach out to the United Standings Improvement Agency on discord.unitedstandings.org