diff --git a/src/lib.rs b/src/lib.rs
index af50db1..fda51b8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -72,7 +72,7 @@ pub trait RateableMut {
     fn sigma_mut(&mut self) -> &mut f64;
 }
 
-#[derive(Debug, PartialEq)]
+#[derive(Debug, PartialEq, Clone)]
 pub struct Rating {
     pub mu: f64,
     pub sigma: f64,