diff --git a/R/project/postprocessing.R b/R/project/postprocessing.R
index a831b19..3ba9973 100755
--- a/R/project/postprocessing.R
+++ b/R/project/postprocessing.R
@@ -84,11 +84,11 @@ maj_ecow_for_list_cheptels <- function(list_cheptels){
   return(res)
 }
 
-
 format_duration <- function(seconds) {
-  h <- seconds %/% 3600
-  m <- (seconds %% 3600) %/% 60
-  s <- seconds %% 60
+  h <- as.integer(seconds %/% 3600)
+  m <- as.integer((seconds %% 3600) %/% 60)
+  s <- as.integer(seconds %% 60)
+  
   sprintf("%02d:%02d:%02d", h, m, s)
 }