How to Calculate YTD Sales for SAME PERIOD LAST YEAR using DAX Expression in Power BI

DAX Expression to Calculate YTD Sales for SAMEPERIODLASTYEAR in Power BI
Scenario:
Suppose We have the Sales Data for 2 consecutive Years 2015 and 2016. From this data the Customer interested to know YTD_Sales for Current Year as well as Same Period of the Last Year.
We can achieve this by the following way.
First We Create the Calculate a measure that Shows the YTD_Sales for the Current Year as follows :
YTD_Sales = TOTALYTD(SUM(FactSales[Gross_Sales]),Tbl_Calendar[Date_Id])
Here, Tbl_Calendar is a related Table whose [Date_Id] has a relation with [Order_Date] of the the [FactSales] Table.
Now based on this Measure, we can calculate the YTD Sales for the SAME PERIOD LAST YEAR using the following DAX Expression.
LY_YTD_Sales = CALCULATE(
                                                    [YTD_Sales],                                                                                                                              SAMEPERIODLASTYEAR(Tbl_Calendar[Date_Id])
                                                   )

Now we can see the YTD_Sales and LY_YTD Sales calculated in below Cross Tab ( Matrix ) Reports.
YTD Sales for FY2015 :

YTD_Sales for FY2016 and LY_YTD_Sales(FY2015) :

Note :
Compare the above two Matrix reports two Check whether the LY_YTD Sales calculating correctly or not.
Next we can create a visualization with Trend Line Chart that shows the Sales Growth Momentum comparison by Month for the Fiscal Year 2015 and 2016.

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Thanks, TAMATAM ; Business Intelligence & Analytics Professional 

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