update CHANGES

CHANGES.rst

@@ -4,7 +4,7 @@ Changelog
 
 v0.49.0 (unreleased)
 --------------------
-Contributors to this version: Trevor James Smith (:user:`Zeitsperre`), Pascal Bourgault (:user:`aulemahal`), Juliette Lavoie (:user:`juliettelavoie`), David Huard (:user:`huard`), Gabriel Rondeau-Genesse (:user:`RondeauG`),, Éric Dupuis (:user:`coxipi`).
+Contributors to this version: Trevor James Smith (:user:`Zeitsperre`), Pascal Bourgault (:user:`aulemahal`), Juliette Lavoie (:user:`juliettelavoie`), David Huard (:user:`huard`), Gabriel Rondeau-Genesse (:user:`RondeauG`), Éric Dupuis (:user:`coxipi`).
 
 Announcements
 ^^^^^^^^^^^^^
@@ -25,6 +25,7 @@ Breaking changes
 * The previously deprecated functions ``xclim.sdba.processing.construct_moving_yearly_window`` and ``xclim.sdba.processing.unpack_moving_yearly_window`` have been removed. These functions have been replaced by ``xclim.core.calendar.stack_periods`` and ``xclim.core.calendar.unstack_periods``. (:pull:`1717`).
 * Indicators ``snw_season_length`` and ``snd_season_length`` have been modified, see above.
 * Estimation of parameters using `_fit_start` for `gamma` and `fisk` has been changed and can affect the results obtained with full-fledged (e.g. "ML") methods. (:issue:`1477`  :pull:`1720`).
+* Zero inflated distributions used in ``xclim.stats.standardized_index`` now appropriately use the probability of zeroes in the calibration data and not the entire dataset. (:issue:`1477`  :pull:`1720`).
 
 Bug fixes
 ^^^^^^^^^