Convert Week No to Date Range

Hi, icdns 

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

Calendar(a calculated table):

Calendar = CALENDAR(DATE(2019,1,1),DATE(2020,12,31))

Calculated column:

Year = YEAR('Calendar'[Date])
Week of Year = WEEKNUM('Calendar'[Date])

You may create a calculated column or a measure as below.

Calculated column:
Date Range column = 
var _mindate = 
CALCULATE(
    MIN('Calendar'[Date]),
    FILTER(
        ALL('Calendar'),
        'Calendar'[Year]=EARLIER('Calendar'[Year])&&
        'Calendar'[Week of Year]=EARLIER('Calendar'[Week of Year])
    )
)
var _maxdate = 
CALCULATE(
    MAX('Calendar'[Date]),
    FILTER(
        ALL('Calendar'),
        'Calendar'[Year]=EARLIER('Calendar'[Year])&&
        'Calendar'[Week of Year]=EARLIER('Calendar'[Week of Year])
    )
)
return
_mindate&" - "&_maxdate

Measure:
Date Range measure = 
var _mindate = 
CALCULATE(
    MIN('Calendar'[Date]),
    FILTER(
        ALL('Calendar'),
        'Calendar'[Year]=SELECTEDVALUE('Calendar'[Year])&&
        'Calendar'[Week of Year]=SELECTEDVALUE('Calendar'[Week of Year])
    )
)
var _maxdate = 
CALCULATE(
    MAX('Calendar'[Date]),
    FILTER(
        ALL('Calendar'),
        'Calendar'[Year]=SELECTEDVALUE('Calendar'[Year])&&
        'Calendar'[Week of Year]=SELECTEDVALUE('Calendar'[Week of Year])
    )
)
return
_mindate&" - "&_maxdate

Result:

Best Regards

Allan

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