diff --git a/app/Http/helpers.php b/app/Http/helpers.php
index 505ce94..8d8cf10 100644
--- a/app/Http/helpers.php
+++ b/app/Http/helpers.php
@@ -10,7 +10,7 @@
 function rand_bool($prob = 50) {
     if ($prob < 0 or $prob > 100) {
         throw new InvalidArgumentException('The value for the probability '.
-          ' must be in a range from 0 to 100.');
+          'must be in a range from 0 to 100.');
     } else if (!is_int($prob)) {
         throw new InvalidArgumentException('rand_bool only accepts integers.');
     }
@@ -19,3 +19,18 @@ function rand_bool($prob = 50) {
 
     return $rand <= $prob;
 }
+
+/*
+ * Return the formatted string representation of a floatng point number.
+ *
+ * The decimal point is a ',', the thousands seperator ist set to '.'.
+ * The number of decimals is 2 by default but can be set by the $decimals
+ * argument.
+ *
+ * @param  integer $decimals Sets the number of decimal points.
+ *
+ * @return string
+ */
+function formatAmount(float $amount, $decimals = 2) {
+    return number_format($amount, $decimals, ',', '.');
+}