diff --git a/src/aes_hash.rs b/src/aes_hash.rs
index 0b9a1d4..7ad9af7 100644
--- a/src/aes_hash.rs
+++ b/src/aes_hash.rs
@@ -252,6 +252,7 @@ impl Hasher for AHasherU64 {
     #[inline]
     fn write_u64(&mut self, i: u64) {
         self.buffer = folded_multiply(i ^ self.buffer, MULTIPLE);
+        self.pad = self.pad.wrapping_add(i);
     }
 
     #[inline]