Cumulative calculation stopped working when using data model in the service

Thanks for GilbertQ's concern about this issue.

Hi, 99_pct 

First, you can test if it works by changing the DAX to what GilbertQ  recommends, or the DAX I provide below below:

Cumulative Budget = 
SUMX(
    FILTER(
        'Month list',
        'Month list'[Month] <= EARLIER('Month list'[Month])
    ),
    'Actuals vs Budget'[Budget]
)

Secondly you need to make sure that the [Month] field is formatted and of the correct type. Because it is not a date field, Power BI may handle it differently on the server side than on the desktop. You can try converting the [Month] field to a date type or make sure it is consistent across all reports.

Or try deleting and recreating the metric in the Source Report and User Report, which can sometimes reset the potential problem.

Sometimes caching issues can also cause inconsistent data, try clearing your browser cache.

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Fen Ling,
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