Whats new added

Author: rbenes

doc/source/whatsnew/v0.25.0.rst

@@ -37,6 +37,7 @@ Other Enhancements
 - :class:`RangeIndex` has gained :attr:`~RangeIndex.start`, :attr:`~RangeIndex.stop`, and :attr:`~RangeIndex.step` attributes (:issue:`25710`)
 - :class:`datetime.timezone` objects are now supported as arguments to timezone methods and constructors (:issue:`25065`)
 - :meth:`DataFrame.query` and :meth:`DataFrame.eval` now supports quoting column names with backticks to refer to names with spaces (:issue:`6508`)
+- :meth:`pandas.core.window.Rolling` supports exponential (or Poisson) window type (:issue:`21303`)
 
 .. _whatsnew_0250.api_breaking: