Field help (RATVATREC) 

The VAT recovery rate cannot be entered. It is loaded with the deduction coefficient.
If the expense originates from the validation of an invoice or validation/entry of an accounting document, the displayed rate is taken from the source document. However, this is not significant: the recovered VAT amount is not recalculated but forced with the total of recovered VAT amounts of attached expenses. However, in case of modification of one of the VAT coefficients, or of the activity sector, the rate is recalculated and used to define the recovered VAT amount.