Working with particular dates/date range in Zendesk reports calculated metrics (Formulas)

1. This Week Tickets (Created)- Count of tickets created between Friday of the previous week and Thursday of the current week.
IF (DATE_DIFF(TODAY(),[Ticket created - Date],"nb_of_days")<=7) THEN [Ticket ID] 
ENDIF

2. Last Week Tickets (Created)-Count of tickets created between two Fridays ago and Thursday of last week.
IF (DATE_DIFF(TODAY(),[Ticket created - Date],"nb_of_days")>7) AND (DATE_DIFF(TODAY(),[Ticket created - Date],"nb_of_days")<=14) THEN [Ticket ID] 
ENDIF

3. Last 4 Week Tickets (Cretated)-Count of tickets created between four Fridays ago and Thursday of the current week.
IF (DATE_DIFF(TODAY(),[Ticket created - Date],"nb_of_days")>7) AND (DATE_DIFF(TODAY(),[Ticket created - Date],"nb_of_days")<=35) THEN [Ticket ID] 
ENDIF

Above are the three metrics I am using to compare Inflow tickets volume of this week(Friday -Thursday) with last week and last 4 weeks volume average.
However while doing analysis the numbers on dashboard keeps changing and I am face challenges to send analysis summary.
I understand that I used DATE_DIFF formula and DATE_DIFF(TODAY(),[Ticket created - Date],"nb_of_days")<=7 is relative dynamic date range and hence numbers keeps changing. I added created date filter to report as below to not include current days tickets. However the numbers keeps decreasing in this weeks tickets count as time passes in current day.

How can I update formulas? for example I am preparing report on 16th Feb(Fri)
I should get count of tickets as pe below ticket creation date and dashboard should be static for one day i.e. 24 hrs. so I can do analysis by drilling into the data and provide summary on it.

This Week Tickets (Created): Count of tickets created from February 9th to February 15th.
Last Week Tickets (Created): Count of tickets created from February 2nd to February 8th.
Last 4 Week Tickets (Created): Count of tickets created from January 19th to February 15th.

This is just one report, but I have many reports based on above formula logic for comparing tickets volume of this week with last week. If I get logic for above, I could implement same in other reports.