DOC: Add whatsnew note

Licht-T · Licht-T · commit b8e84e3688ce · 2017-11-26T00:12:37.000+09:00
diff --git a/doc/source/whatsnew/v0.21.1.txt b/doc/source/whatsnew/v0.21.1.txt
@@ -98,7 +98,7 @@ Plotting
 Groupby/Resample/Rolling
 ^^^^^^^^^^^^^^^^^^^^^^^^
 
--
+- Bug in ``rolling.var`` which calculation is inaccurate with a zero-value array (:issue:`18430`)
 -
 -
 

Original file line number	Diff line number	Diff line change
`@@ -98,7 +98,7 @@ Plotting`
`98`	`98`	`Groupby/Resample/Rolling`
`99`	`99`	`^^^^^^^^^^^^^^^^^^^^^^^^`
`100`	`100`
`101`		`--`
	`101`	+- Bug in ``rolling.var`` which calculation is inaccurate with a zero-value array (:issue:`18430`)
`102`	`102`	`-`
`103`	`103`	`-`
`104`	`104`