diff --git a/macros/tests/is_valid_percentage.sql b/macros/tests/is_valid_percentage.sql
new file mode 100644
index 0000000..4e90ab9
--- /dev/null
+++ b/macros/tests/is_valid_percentage.sql
@@ -0,0 +1,10 @@
+/*
+The opinionated definition of a valid percentage for this macro:
+- It is between 0 and 1 (including 0 and 1 as valid values).
+*/
+{% test is_valid_percentage(model, column_name) %}
+    with validation as (select {{ column_name }} as value from {{ model }})
+    select *
+    from validation
+    where value > 1 or value < -1
+{% endtest %}