diff --git a/htdocs/compta/tva/quadri_detail.php b/htdocs/compta/tva/quadri_detail.php
index c622881d273..d4ccbf98804 100644
--- a/htdocs/compta/tva/quadri_detail.php
+++ b/htdocs/compta/tva/quadri_detail.php
@@ -447,7 +447,7 @@ else
 				$ratiopaymentinvoice=1;
 				if ($modetax == 0)
 				{
-					if (isset($fields['payment_amount']) && $fields['ftotal_ttc']) $ratiopaymentinvoice=($fields['payment_amount']/$fields['ftotal_ttc']);
+					if (isset($fields['payment_amount']) && price2num($fields['ftotal_ttc'])) $ratiopaymentinvoice=($fields['payment_amount']/$fields['ftotal_ttc']);
 					print '<td class="nowrap" align="right">';
 					//print $fields['totalht']."-".$fields['payment_amount']."-".$fields['ftotal_ttc'];
 					if ($fields['payment_amount'] && $fields['ftotal_ttc'])