diff --git a/prune_data.sh b/prune_data.sh
index ea0bb3c..d5774e5 100755
--- a/prune_data.sh
+++ b/prune_data.sh
@@ -1,7 +1,6 @@
-
 #!/bin/bash
 
-function usage {
+usage() {
     echo -n "Usage: ${0}"
     echo -n " -d <root_dir>"
     echo -n " -D <older than time criteria> (example: '2 days ago')"