diff --git a/src/stats/totalDuration.ts b/src/stats/totalDuration.ts
index d76d8d5..54c95b5 100644
--- a/src/stats/totalDuration.ts
+++ b/src/stats/totalDuration.ts
@@ -3,4 +3,4 @@ import { Interval } from "../ast";
 import { Seconds } from "../types";
 
 export const totalDuration = (intervals: Interval[]): Seconds =>
-  new Seconds(sum(map((i) => i.duration.value, intervals)));
+  new Seconds(sum(map((interval) => interval.duration.value, intervals)));