diff --git a/src/types.ts b/src/types.ts
index 56807051..c14094d5 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -235,6 +235,17 @@ export type NumberOfMilliseconds = number
  */
 export type Integer = number
 
+/**
+ * Convenience type alias, that allows to write this:
+ *
+ * data: NullableNumber[]
+ *
+ * instead of this:
+ *
+ * data: (number | null)[]
+ */
+export type NullableNumber = number | null
+
 /**
  * Used as a compact representation of truthy value.
  * undefined ('' or other short falsy value) should be used as falsy value.