diff --git a/src/datetime/mod.rs b/src/datetime/mod.rs
index 28cc64ab79..4783e87253 100644
--- a/src/datetime/mod.rs
+++ b/src/datetime/mod.rs
@@ -594,7 +594,7 @@ impl<Tz: TimeZone> DateTime<Tz> {
     ///
     /// # Errors
     ///
-    /// Returns `None` if `base < self`.
+    /// Returns `None` if `base > self`.
     #[must_use]
     pub fn years_since(&self, base: Self) -> Option<u32> {
         let mut years = self.year() - base.year();
diff --git a/src/naive/date/mod.rs b/src/naive/date/mod.rs
index 9257ddab32..34101e0d84 100644
--- a/src/naive/date/mod.rs
+++ b/src/naive/date/mod.rs
@@ -1136,7 +1136,7 @@ impl NaiveDate {
     ///
     /// # Errors
     ///
-    /// Returns `None` if `base < self`.
+    /// Returns `None` if `base > self`.
     #[must_use]
     pub const fn years_since(&self, base: Self) -> Option<u32> {
         let mut years = self.year() - base.year();