Upgrade Bonuses not calculating

[ElMacho]

I have 50% upgrade cost reduction (like 6 or 7 different units) Plus another 9% from the cement factory and it only shows 37% upgrade reduction. The concrete plant only shows building cost reduction and does not include upgrade cost reduction in profile screen.

Anyone else add their bonuses up and see if it's right? Or is this another "display glitch?"

[Thorm V2]

They are multiplicative not additive. Can't add things that couldn't logically happen- i.e., if you had enough boosts that would add up to over 100%- your upgrades would be free.

[ElMacho]

Makes sense thanks for the clarification.

[Hub_Master_General]

I have the same problem. Gree says it should have been taken care of with release 4.2 but I'm not seeing any change myself.

[Kefa]

I have the same problem. Gree says it should have been taken care of with release 4.2 but I'm not seeing any change myself.

Each -10% bonus reduces the cost by 10%, but think about the math. It's a reduction, not an addition.

Start with 100, reduce it by 10% and it's now 90.

Reduce 90 by 10%, and it's now 81.

Reduce 81 by 10%, and it's now 72.9

Another 10% makes it 65.61

Another 10% Makes it 59.049.

So 5x 10% reduction bonuses will net a total reduction of ~41%

[Maz]

http://forums.gree.net/showthread.php?42885-Faction-boost-bonuses

Explains how the multiplicative and additive boosts work with examples given.