System cost index not being calculated correctly?

I’m not sure if this is a known bug. Apologies if it is.

It seems that the System Cost index calculation (Job Gross Cost) is a bit off. For example, in the case of a Micro Auxiliary Power Core I with an estimated value of 355 178 ISK It should be 6854 ISK (or 6855 rounded), but shows as 6864 ISK. 9-10 ISK feels too far off to be a rounding error :thinking:.

Moreover, this seems to be add up for each consecutive run, causing non-trivial margin errors.

Example image with 900 units of Micro Auxiliary Power Core I

One speculation is that that the system cost index has a float value of something like 0.019324, and that it’s not rounding the value when computing the costs, only when displayed.

I checked the /industry/systems ESI endpoint, which does respond with rounded values.

Expected Behaviour:

The system cost index is calculated more exactly with the percentage value displayed in the UI (rounded to 2 decimals).

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It is calculated correctly, the % is rounded down in ur case to precision of 2 digits after the comma. E.g. While it says its 1.93% its like something more like 1.932%, it just doesnt show in the ingame UI

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What Holo says.

Some numbers as example:

1.92500% of 355178 is 6837
1.93000% of 355178 is 6854
1.93499% of 355178 is 6873

Each of these percentages rounded to two decimals is 1.93%.

In other words, nothing is wrong with 6864, as it is well within the range of 6837 to 6873 that you could get with numbers rounded to 1.93%.

Yep, the displayed 1.93% seems to be rounded while the real number is used for calculations.