diff --git a/tools/find-inactive-collaborators.mjs b/tools/find-inactive-collaborators.mjs
index 06ad60d7ff46fd..4d7802a0ed30f5 100755
--- a/tools/find-inactive-collaborators.mjs
+++ b/tools/find-inactive-collaborators.mjs
@@ -8,7 +8,7 @@ import cp from 'node:child_process';
 import fs from 'node:fs';
 import readline from 'node:readline';
 
-const SINCE = +process.argv[2] || '18 months ago';
+const SINCE = process.argv[2] || '18 months ago';
 
 async function runGitCommand(cmd, mapFn) {
   const childProcess = cp.spawn('/bin/sh', ['-c', cmd], {