Official manufacturing calculation formular by ccp (ingame stations)

I try to write a sheet for calculating the manufacturing cost for a given blueprint.

Example 1:
BP ME: 8%
Structure: 1%
Rigs: 4,2%
8 Units: 8 * 0.92 * 0.99 * 0.958 ~ 7 → is correct (shown by job cost within manufacturing window)

Example 2:
BP ME: 9%
Structure: 1%
Rigs: 4,2%
7 Units: 7 * 0.91 * 0.99 * 0.958 ~ 6 → not correct (still 7 is shown within the manufacturing window)

I also tried it with rounding errors (ceil >0.37 and floor <0.36666). This works for both examples but not exactly for larger numbers…

What I tried: round( round( round(7 * 0.91) * 0.99) * 0.958)

So, do you know the formular CCP uses? Would be awesome!

Thanks in advance!

Edit: The rounding boundaries do not work.

Example 3:
BP ME: 8%
Structure: 1%
Rigs: 4,2%
16 Units: round ( … ) ~ 15 → not correct (it shows 14)

When you say round, think truncate. It will never round up! Also bonuses are applied in series - each bonus applies to the remainder from the previous calculation. Thus the 1% structure bonus only applies if there are 100 (or more) units required after other bonuses are applied (I don’t know the order if there are multiple bonuses). Bonuses are also per job, not per run.

I tend to make several thousand advanced components per job so the ME rig is worthwhile. For T2 module production which use a small number of advanced components per run and you are limited to 10 run BPCs, an ME bonus isn’t very useful.

Could you give me an example what do you mean? Truncation does not make sense for my given Example 2. Even if I applay those percentages one after another… it doesnt work.

I understand that those percentages apply at one run and then again at the next one… but my examples only refer to one single run. And even in this easy case… I could not find any formular which fits the standard amount and then the amount shown in the manufacturing window.

Mind, I never did look into how material efficiency in EVE industry jobs work, so it’s not unlikely I’m wrong in some way, but let me get an example of how your results make sense with @Do_Little 's truncation.

First example: 13,2% material efficiency*
0,132 × 8 = 1,056
Or truncated: 1 item saved in a batch of 1, or 10 items saved in a batch of 10, or 105 saved in a batch of 100 and 1056 items saved in a batch of 1000. It makes sense to run large batch jobs for the highest efficiency.

Second example: 14,2%
0,142 × 7 = 0,994
Truncated: you save 0 items, unless you run a larger batch in which case you save almost one item every run, 994 on a batch of 1000

Third example: 13,2%
0,132 × 16 = 2,112
Which explains why you only need 14.

*I have no idea if I can just add the percentages together here, so correct me if I’m wrong. It seems to get the right results though.

For your example 2:
You are saving 9% of 7 which is less than 1 so truncates (or rounds down) to 0
then you are saving 1% of 7 still less than 1 so truncates (or rounds down) to 0
last you are saving 4.2% of 7 which is still less than 1 so truncates (rounds down) to 0

Total saving is 0 + 0 + 0 so you still need 7 units.

If you submitted a job for 2 runs - requiring 14 units of material, the BP ME bonus calculation would be 14*.9 = 1.26 which truncates to 1 so you would save 1 unit requiring 13 total instead of 14. The other bonuses would still not apply. You would need 4 runs to benefit from the rig bonus and 15 runs to benefit from the structure bonus - maybe more depending how they stack.

@Do_Little From your example I guess I made a mistake in adding those saving percentages together? Just checking, I have never done any manufacturing yet where I needed to pay attention to the %.

Actually, on closer examination, your examples show that adding the bonuses does work.

8+1+4.2 = 13.2% of 8 is 1.05 which will save you 1 unit

For your 2nd example
9+1+4.2 = 14.2% of 7 is .994 so you save nothing.

Ok, so I tried your version of truncation which works for those single job runs. Now I tried to apply it on other jobs with way larger numbers:

Example 4:
ME: 10%
Structure: 1%
Riggs: 4.2%
Units: 473,141
Expected value after applying bonuses: 403,863

Formular with truncation:

x_me = 473,141 - truncate(473,141 * 0.1)
x_rig = x_me - truncate(x_me * 0.042)
x_st = x_rig - truncate(x_rig * 0.01)
x_st = 403,864

So, it’s not the correct value (missing 1 unit)
Now I tried rounding:

x_me = 473,141 - round(473,141 * 0.1)
x_rig = x_me - round(x_me * 0.042)
x_st = x_rig - round(x_rig * 0.01)
x_st = 403,863

So, I will investigate for other values… will see if eve is rounding properly.

Edit: Rounding won’t work for smaller values -.-

Edit 2: Applaying all bonuses as summation works for smaller values but not for larger values!? Wtf Eve… give me a doc about ur math!!!

Edit 3:
If you applay all bonuses as summation on Example 4 you will receive a value of 401,224.

Okay, so it’s pretty clear adding all bonuses doesn’t work. :smiley:

Could this link help? They’re talking about the same calculation there it seems. And they’re using not truncate, nor round, but round up.

This should give the correct values for all your examples:

Example 1:
8 × (1-0,08)(1-0,01)(1-0,042) = 6,994944 → rounded up 7

Example 2:
16 × (1-0,08)(1-0,01)(1-0,042) = 13,989888 → rounded up 14

Example 3:
7 × (1-0,09)(1-0,01)(1-0,042) = 6,0414354 → rounded up 7

Example 4:
473141 × (1-0,1)(1-0.042)(1-0.01) = 403862,748498 → rounded up 403863

Thank you for this post. This kinda work. Sometimes it is missing 3 to 6 Units of something… but it seems to work with smaller numbers. So… it is still not the correct formular. However, I am glad I can now calculate my stuff. CCP should cover those things in a spreadsheet game :wink: