diff --git a/src/bitboard.rs b/src/bitboard.rs
index b2b5083..cbac136 100644
--- a/src/bitboard.rs
+++ b/src/bitboard.rs
@@ -4,7 +4,7 @@ use static_assertions::const_assert;
 // quick explanation for the dual-nature of [`BitBoard`]
 // There's both a `bitvec` impl (which is variable length)
 // and a `native` impl which uses a u64 as the backing type
-// the `native` impl is ~15% faster (in non-BitBoard specific benchmarks)
+// the `native` impl is ~15-25% faster (in non-BitBoard specific benchmarks)
 // `bitvec` is only really useful if you're using esoteric board sizes
 
 #[cfg(feature = "bitvec")]