diff --git a/src/Yasumi/Yasumi.php b/src/Yasumi/Yasumi.php
index 25ed5b95a..c2c98af91 100644
--- a/src/Yasumi/Yasumi.php
+++ b/src/Yasumi/Yasumi.php
@@ -197,7 +197,7 @@ public static function createByISO3166_2(
     /**
      * Returns a list of available holiday providers.
      *
-     * @return array<string> list of available holiday providers
+     * @return array<string, array<array-key, string>|string|null> list of available holiday providers
      *
      * @throws \ReflectionException
      */