diff --git a/app/utils/template-operators.js b/app/utils/template-operators.js
index f399841..1e32efb 100644
--- a/app/utils/template-operators.js
+++ b/app/utils/template-operators.js
@@ -1,3 +1,3 @@
 export const eq = (a, b) => a === b;
-export const maybe = (val, def = 'X') => (val ? val : def);
+export const maybe = (val, def = 'X') => (val >= 0 ? val : def);
 export const formatDate = (date) => Intl.DateTimeFormat().format(date);