As far as i know i can add space for same alias names to make it but if we have any other process then it will be great..
Understand what you are doing when you write a new Calculation - you create an additional column of in the table that underlies the viz - its like adding a column of data to an excel spreadsheet - so multiple columns in the sheet can not have identical names - for example you use those names in other calculations - but you can make them unique with spaces and special characters -
You know your client better than we would but it seems a little confusing to have a common name on fields that could represent a MTD or YTD check as your narrative suggests
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