matplotlib
diff --git a/‎lib/matplotlib/axis.py‎
Lines changed: 6 additions & 7 deletions b/‎lib/matplotlib/axis.py‎
Lines changed: 6 additions & 7 deletions
diff --git a/‎lib/matplotlib/units.py‎
Lines changed: 15 additions & 0 deletions b/‎lib/matplotlib/units.py‎
Lines changed: 15 additions & 0 deletions
@@ -1565,6 +1565,10 @@ def have_units(self):
         return self.converter is not None or self.units is not None
 
     def convert_units(self, x):
+        # If x is natively supported by Matplotlib, doesn't need converting
+        if munits.ConversionInterface.is_natively_supported(x):
+            return x
+
         if self.converter is None:
             self.converter = munits.registry.get_converter(x)
 
@@ -1573,13 +1577,8 @@ def convert_units(self, x):
         try:
             ret = self.converter.convert(x, self.units, self)
         except Exception as e:
-            # If x is already number like, converters other than
-            # DecimalConverter may raise error, so check here to walk around.
-            if munits.ConversionInterface.is_numlike(x):
-                return x
-            # Otherwise, the conversion fails
-            raise munits.ConversionError('Failed to convert value(s) to '
-                                         f'axis units: {x!r}') from e
+            raise munits.ConversionError('Failed to convert value(s) to axis '
+                                         f'units: {x!r}') from e
         return ret
 
     def set_units(self, u):
 
@@ -134,6 +134,21 @@ def is_numlike(x):
         else:
             return isinstance(x, Number)
 
+    @staticmethod
+    def is_natively_supported(x):
+        """
+        Return whether *x* is of a type that Matplotlib natively supports or
+        *x* is array of objects of such types.
+        """
+        # Matplotlib natively supports all number types except Decimal
+        if np.iterable(x):
+            # Assume lists are homogeneous as other functions in unit system
+            for thisx in x:
+                return (isinstance(thisx, Number) and
+                        not isinstance(thisx, Decimal))
+        else:
+            return isinstance(x, Number) and not isinstance(x, Decimal)
+
 
 class DecimalConverter(ConversionInterface):
     """