Daedric Armor Rating Question

[ESH]

So I am level 22 with my current character and I just acquired the last pieces of my Daedric armor set. However, none of the pieces seem to match the armor rating which this site's page would suggest it to have. My armor is rated as:

Boots/Gauntlets/Helmet = 4
Greaves = 9
Cuirass = 15
I also have the shield, but I wasn't using it or really planning on using it either so I left it in one of my houses chests and I can't remember which one at the moment so I don't know what it's armor rating is.

As this site's Oblivion: Armor page shows, the armor rating for a full set of Daedric Armor should be 75, minus the 22.5 for the shield, and it should be 52.5
Mine is 36... So what am I missing?
I don't know if any of this matters but my Heavy Armor skill is at 75, my Endurance attribute is 91, and my Strength is maxed at 100. I've looked at my active status effects just to see if anything was amiss, but I have no negative status effects at all. I'm relatively new to this game, having started with Skyrim, so it's definitely possible that I am over-looking something. But I am definitely really confused. Everything I have looked up indicates my armor rating should be much higher than it is.

Any help or clarification would be greatly appreciated, and thank you in advance.

[ESH]

Just after I posted this, I decided to check out some of my other armor sets to see if this was a consistent issue. And it seems like it is. My Crusader's Armor from the KotN expansion has a total armor rating (including shield) of 57, whereas the page for it on this site shows that at level 21+ it should be 74.75.

[Dark Spark]

Your skill in Heavy Armor is a direct percentage of the armor's maximum value. With your HA skill at 75, you'll have 75% of the armor rating listed in the wiki.

Another consideration: repair of armor. In Oblivion, armor and weapons wear down, and the effectiveness drops.

[ESH]

I made sure that they were fully repaired to 100%.

So is it my Heavy Armor rating that is to blame? I thought the value shown on the site was the base value for the armor; not factoring in things like skills, attributes, abilities, etc. Or was I just misunderstanding that?

Thank you for your reply

[Chicken Slayer]

It is your skill. People frequently ask the same question about weapons e.g. "why is Honorblade only giving me 12 damage when the wiki says it should be 23?"

[Dark Spark]

The listed stats in the wiki are the maximum, what you get with a skill at 100 points.

In addition to that, armor rating is capped at 85. You can't get any higher, be it by enchantment, skill or armor.