diff -r 0aef416dbceb -r f4e00869f39f www/prod_print.php
--- a/www/prod_print.php	Fri Apr 17 11:29:37 2020 +0200
+++ b/www/prod_print.php	Sat Apr 18 11:12:28 2020 +0200
@@ -896,7 +896,7 @@
                 $this->Cell(45,5,'Lageren einde',0,0,'L',true);
                 $this->Cell(45,5,$row['package_date'],0,0,'L',true);
 		$this->Cell($vul,5,'',0,0,'L',false);
-		$svg = 100 * (floatval($row['brew_fermenter_sg']) - floatval($row['fg'])) / (floatval($row['brew_fermenter_sg']) - 1);
+		$svg = calc_svg(floatval($row['brew_fermenter_sg']), floatval($row['fg']));
 		$this->Cell(45,5,'Schijnbare vergistingsgraad',0,0,'L',true);
                 $this->Cell(45,5,sprintf("%.1f",$svg).'%',0,0,'L',true);
                 $this->Ln();