diff --git a/postgres/determining-the-age-of-things.md b/postgres/determining-the-age-of-things.md
index 7468f9b..a093506 100644
--- a/postgres/determining-the-age-of-things.md
+++ b/postgres/determining-the-age-of-things.md
@@ -25,3 +25,5 @@ date of death and then date of birth:
 --------------------------
  57 years 10 mons 14 days
 ```
+
+h/t Josh Davey