DAX calculateMonthlyTotal Function

/*
Function: calculateMonthlyTotal
Purpose: Sums the weekly total amount for each month from a given table where the date column is called reporting week
Parameters: 
1. table - The table containing the weekly total amount and reporting week column
2. reportingWeekColumn - The name of the date column in the table
Return Type: Table
Exceptions: None
*/

calculateMonthlyTotal = 
SUMMARIZE(
    table,
    YEAR(table[reportingWeekColumn]),
    MONTH(table[reportingWeekColumn]),
    "Monthly Total", SUM(table[WeeklyTotalAmount])
)

Usage Example:

Suppose we have a table named 'Sales' with columns 'ReportingWeek' and 'WeeklyTotalAmount'. We can utilize the calculateMonthlyTotal function to sum the weekly total amount for each month as follows:

MonthlyTotal = calculateMonthlyTotal(Sales, "ReportingWeek")

This function will create a new table showing the monthly total amount for each month based on the weekly total amount in the 'Sales' table.