Add mean payment by month

1 files changed, 4 insertions, 0 deletions

diff --git a/src/client/elm/Utils/List.elm b/src/client/elm/Utils/List.elm
index 4886418..cc57d9f 100644
--- a/src/client/elm/Utils/List.elm
+++ b/src/client/elm/Utils/List.elm
@@ -1,5 +1,6 @@
 module Utils.List exposing
   ( groupBy
+  , mean
   )
 
 import Dict
@@ -11,3 +12,6 @@ groupBy f xs =
         in  Dict.insert (f item) (item :: groupItems) dict
   in  List.foldr addItem Dict.empty xs
         |> Dict.toList
+
+mean : List Int -> Int
+mean xs = (List.sum xs) // (List.length xs)