[3.21] Infinite Vaal Volcanic Fissure 150M+ DPS ft. Hateforge [ALL Content Viable] [Crucible Only]

Hi, I'm making this build now (great build by the way, thanks for posting!) and I'm also having some trouble with the rage cost. The number in game does not always seem to round up when I've tried it.

I used this setup: Main link: Vaal Volcanic Fissure - Concentrated Effect (1.4) - Elemental Damage with Attacks (1.3) - Trinity (1.4) - Increased Critical Damage (1.3) - Vicious Projectiles (1.3) - Energy Leech (1.3). Hateforge: 15% reduced rage cost of skills. 60 Max rage (Berserking notable).

So the formula would be:
rage cost = (25 + 3 * (1.4 * 1.3 * 1.4 * 1.3 * 1.3 * 1.3)) * 0.85 ≈ 35.52
Which should round up to 36. But in game it costs 35.
If I change one of the 1.3 multiplier support gems to a 1.4:
rage cost = (25 + 3 * (1.4 * 1.4 * 1.4 * 1.3 * 1.3 * 1.3)) * 0.85 ≈ 36.62
Then it does cost 37 rage in game.

So it looks like the game didn't round up the cost in the first calculation, but it did in the second. Does anyone know why this is happening? I don't think I have any other sources of increased or reduced skill cost. I tested it with very little gear: https://pobb.in/_MADTFO-EnJK

Edit: It seems to be some sort of rounding error. I think the setup I detailed above just doesn't work. You might need 14 or 13% on your Hateforge, but I haven't been able to test it in game so I can't be sure. If anyone is using this setup with a rage cost of 36 in game, please let me know.