Hi Jeff,
Thanks for your reply. So upon looking into it further, the CoverageEffectiveDateKey is actually a foreign key that has been set to the INT datatype, which I traced from table to table of different SSIS packages and ultimately, it appears to pull from a datetime field from another table. Regarding the calculation, I believe an integer value for months is intended to be used. Please let me know if I can further clarify. Thanks.