CSV export supplier invoice booked by bank ledger

Hi
Here happens something strange. When making an CSV export from the ledger of suppliers invoices, i get negatieve figures.
Although on screen it seems OK.
That way you never get an good reporting of the ledger.
Look at some printscreens I have made.
Does anyone have an idea?

La pièce jointe Schermafdrukvan2018-05-2712-30-26.png est absente ou indisponible

Schermafdrukvan2018-05-2712-29-25.png