The wiki (1/8 and 1/6) are both wrong, these have not been nerfed and are not an actual fraction, you regen 25/s no matter how much moonwalk you have in your loadout.
old moonlight was 200 before the nerf, and 1/8th of that is 25
you consume 33.33 moonlight no matter how much moonwalk you have.
I have a highly detailed video guide on all regeneration cards, check the timestamps to skip to your favorite section
Also I have a written guide with that math done:
just incase you don't want to check the guide, I've copied the math here.
Math regarding io
In this scenario, Io is pocketing a 2200 HP champion without taking into account any abilities for simplicity's sake, and going VS a champion that deals 1200 damage per second (such as Andro).
Io now heals for 150 every 0.15 seconds meaning she heals for 1000 every 1 second. I'm ignoring how long a pocket can last, moonwalk has been changed so that you can have a maximum of 210 moonlight (base is now 150 and moonwalk is buffed to 8% per level), so basically Io now has about 6 seconds of constant healing before recharging, so keep that in mind. Now let's apply io's DR+Healing 15% of 1200 is 180, meaning Andro now only deals 1020/s
with 0 Caut (for whatever reason), Io heals for 1000/s meaning the damage dealt is 20/s
with caut 1 she heals for 750/s => damage dealt = 270/s (TTK = 8.14 seconds)
with caut 2 she heals for 500/s => damage dealt = 520/s (TTK = 4.23 seconds)
with caut 3 she heals for 250/s => damage dealt = 770/s (TTK = 2.87 seconds)
This is a very big early game buff for Io (3 more full seconds of being alive to a squishy compared to last patch!), the end game TTK hasn't changed much (was 2.7 seconds, now it's 2.87).
What about NOT using Godess Blessing? (why would you though?), let's look at life link because people think it's the #1 talent for Io's own survival (not my opinion at all, to me Life Link is a throw pick).
I'm Assuming both Io and Luna are healing the target for no reason. without Caut, Io heals for 1000/s and Luna heals for 200/s which means a total of 0 damage is dealt to whomever you are pocketing (better than GB by 20/s wow!).
with caut 1, Io heals for 750/s and Luna heals for 150/s => 1200-900 = 300 dps (TTK 7.33 seconds)
with caut 2, Io heals for 500/s and Luna heals for 100/s => 1200-600= 600 dps (TTK 3.66 seconds)
with caut 3, Io heals for 250/s and Luna heals for 5/s => 1200-300= 900 dps (TTK 2.44 seconds)
so when the end game comes the difference between Godess Blessing and Life Link while both Io and Luna are healing the target, is 0.43 seconds
let's remove Luna because in reality luna's not going to be healing a squishy most of the time since Life Link players keep her for personal protection.
NOTE: this is also Sacrifice's stats, the worst talent on Io
with caut 1, Io heals for 750/s => 1200-750 = 450 dps (TTK 4.88 seconds)
with caut 2, Io heals for 500/s => 1200-500= 700 dps (TTK 3.14 seconds)
with caut 3, Io heals for 250/s => 1200-250= 950 dps (TTK 2.31 seconds)
This is where Life Link's numbers fall short of Godess Blessing, yes, Life Link heals in a radius, but if you think it lets you multi task your healing then think again, Luna heals for 50/s late game, that's nothing, pushing the payload heals for that much (did you know that?).
don't be fooled by end game numbers, who cares if you did only 100k healing when the enemy did 120k?
in reality you kept your team alive longer to do more, pushed with Luna (she auto climbs the payload now), and put some extra damage on enemies to recharge your moonlight.