Watefall charts and formating data

Hi Zalexatwork,

It seems like a common multiple date fields analysis requirements, you can refer to the following link start date, end date parts if help:

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In addition, you can also try to create a bridge table to expand all the detail records in the date ranges and mapping with raw table records:
Solved: Spread revenue across period based on start and en... - Microsoft Power BI Community
Regards,

Xiaoxin Sheng