diff --git a/types/index.d.ts b/types/index.d.ts
index af4e3a3..860b045 100644
--- a/types/index.d.ts
+++ b/types/index.d.ts
@@ -1,3 +1,3 @@
 export function log(text: string): boolean;
 export function setup(obj: any): void;
-export function deleteLog(howManyDaysAgo: number);
+export function deleteLog(howManyDaysAgo: number): void;