First question. Are your dates actually SAS date values or character. I ask because most of the time SAS date displays would show 02/01/18 instead of 2/1/18.
Second does your data cross calendar year? If so by Month then do you mean all January data or each year's January?
Instructions here: https://communities.sas.com/t5/SAS-Communities-Library/How-to-create-a-data-step-version-of-your-data-AKA-generate/ta-p/258712 will show how to turn an existing SAS data set into data step code that can be pasted into a forum code box using the {i} icon or attached as text to show exactly what you have and that we can test code against.
Also a data step means that we do not need to ask if a value is character or numeric.
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