In MySQL utilizing the Transform property, my where clause is not delivering the expected results.

In MySQL utilizing the Transform property, my where clause is not delivering the expected results.  I cannot limit the data I am pulling in thus using the transform property to only look at the date from 01-2016.  Here is a snippet of the code:  

SELECT
DATE_FORMAT(p.`date`,'%m-%Y') AS Date,
p.`Campaign`,
p.`Cost`,

CASE WHEN p.`Campaign` LIKE '%Something%' THEN 'Nothing'
WHEN p.`Campaign` LIKE '%AB%' THEN 'CD'
WHEN p.`Campaign` LIKE '%DE%' THEN 'FG'
WHEN p.`Campaign` LIKE '%ST%' THEN 'XV'
WHEN p.`Campaign` LIKE '%Change%' THEN 'Protect'
Else 'Logo'
END as Grouping

FROM `ppc_baseline` p

Where p.`Date` > 12-2015 AND p.`Cost` > 0

ORDER BY p.`Date` ASC