Hi @kanupindi ,
There seem to be some idiosyncracies with the date function in report designer. You can use CDate to cast 1/1/1900 as a date, but I had to adjust the first date forward to 5/7/1900 to get the correct date as an end result. Not sure why it should be 5/7/1900, but this formula does seem to work:
=DateAdd(CDate('5/7/1900'), 'w', DateDiff('w', CDate('1/1/1900'), CDate(Today()))-1)
A different approach is to build the formula based on the day of the week. The idea is to subtract a certain number of days based on the day of the week.
Beware though. In my experiments the DayOfWeek function operates differently in a GI vs the Report Designer. In a GI the DayOfWeek function returns 1-7 beginning with Sunday. In the Report Designer, the DayOfWeek function appears to return 0-6 beginning with Monday.
In the Report Designer, I was able to get the correct behavior using this formula:
=IIf(DayOfWeek(Today())=0, DateAdd(Today(), 'd', -13), DateAdd(Today(), 'd', -1*DayOfWeek(Today())-6))
Hope that helps!
Laura