diff -r 0aef416dbceb -r f4e00869f39f www/prod_r_yeast.php
--- a/www/prod_r_yeast.php	Fri Apr 17 11:29:37 2020 +0200
+++ b/www/prod_r_yeast.php	Sat Apr 18 11:12:28 2020 +0200
@@ -101,7 +101,7 @@
 
 			$og = floatval($row['brew_fermenter_sg']);
 			$fg = floatval($row['fg']);
-			$svg = 100 * ($og - $fg) / ($og - 1);
+			$svg = calc_svg($og, $fg);
 
 			$name = iconv('UTF-8','windows-1252',$row['name']);
 			$this->SetX($this->TableX);