Total previous period dynamically

With time intelligence and date calendar you can try

YTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESYTD(('Date'[Date]),"12/31"))
This Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESYTD((ENDOFYEAR('Date'[Date])),"12/31"))

Last YTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESYTD(dateadd('Date'[Date],-1,Year),"12/31"))
Last YTD complete Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESYTD(ENDOFYEAR(dateadd('Date'[Date],-1,Year)),"12/31"))
Last to last YTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESYTD(dateadd('Date'[Date],-2,Year),"12/31"))

Year behind Sales = CALCULATE(SUM(Sales[Sales Amount]),dateadd('Date'[Date],-1,Year))

In case you do not want to use date slicer

-- Force today filter
YTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESYTD(('Date'[Date]),"12/31"),'Date'[Date]<=today())

Last YTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESYTD(dateadd('Date'[Date],-1,Year),"12/31"),'Date'[Date]<=date(year(today()-1),month(today()),day(today())))

-- with filter

YTD Sales 1= CALCULATE(SUM(Sales[Sales Amount]),DATESYTD(('Date'[Date]),"12/31"))

Last YTD Sales 1 = CALCULATE(SUM(Sales[Sales Amount]),DATESYTD(dateadd('Date'[Date],-1,Year),"12/31"))

--combine

final YTD = if(isfiltered(Date[Month Year]) || isfiltered(Date[Year]) || isfiltered(Date[Date]),[YTD Sales 1],[YTD Sales])
final LYTD = if(isfiltered(Date[Month Year]) || isfiltered(Date[Year]) || isfiltered(Date[Date]),[Last YTD Sales 1],[Last YTD Sales])

To get the best of the time intelligence function. Make sure you have a date calendar and it has been marked as the date in model view. Also, join it with the date column of your fact/s. Refer :
https://radacad.com/creating-calendar-table-in-power-bi-using-dax-functions
https://www.archerpoint.com/blog/Posts/creating-date-table-power-bi
https://www.sqlbi.com/articles/creating-a-simple-date-table-in-dax/

See if my Time Intelligence the Hard Way provides a different way of accomplishing what you are going for.

https://community.powerbi.com/t5/Quick-Measures-Gallery/Time-Intelligence-quot-The-Hard-Way-quot-TITHW/m-p/434008

Hi, noliverte 

Based on your description, I created data to reproduce your scenario.

Table:

Calendar(a calculated table):

Calendar = CALENDARAUTO()

Then you may create a measure as follows.

Total Session LY all day = 
CALCULATE(
    SUM('Table'[Sessions]),
    DATESBETWEEN(
        'Calendar'[Date],
        DATE(YEAR(TODAY())-1,1,1),
        TODAY()
    )
)

Today is 3/10/2020. So the measure doesn't include sessions for 3/11/2020 and 3/31/2020. Here is the result:

Best Regards

Allan

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.