Imagine following situation:
Total wordcount for the job is 404.
It is split into two parts. Then on the Word count tab for each job the reported word count is 202. This number is also used to calculate the cost of each job.
One get curious how come both parts of the split file have exactly the same number of words. It turns out that the actual number of words in each part will very likely be not 202 but for example 300 and 104.
Why is that?
Splitting is not suited for wordcounting and invoicing, splitting is suited for internal translation when there's no need to invoice anything.
The system is set up to calculate the word count as described here: https://wordbee.zendesk.com/hc/en-us/articles/216111048-Word-count-for-split-document
In the situation above workaround could be to export the xliff of each job and launch again the word count to have the accurate word count.