I'm trying to create a quick filter based off of a case expression and I'm running into some trouble because the dates overlap as you can see below. When I click on the first section it works great but when I click on 'Aug 2018 - Oct 2018' it only gives me Oct's numbers because August and September are already in July - Sept filter. How can I get this to show all 3 months based on what is selected? I know I can do them all in individual case expressions but then how do I combine them all into one quick filter?
CASE
WHEN `PostedDate` >= CAST('2018-07-01' as DATE) AND `PostedDate` <= CAST('2018-09-30' as DATE) THEN 'Jul 2018 - Sep 2018'
WHEN `PostedDate` >= CAST('2018-08-01' as DATE) AND `PostedDate` <= CAST('2018-10-31' as DATE) THEN 'Aug 2018 - Oct 2018'
WHEN `PostedDate` >= CAST('2018-09-01' as DATE) AND `PostedDate` <= CAST('2018-11-30' as DATE) THEN 'Sep 2018 - Nov 2018'
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