Categorize and count each using Formula Workshop

Hi, I am trying to categorize all records like this

Formula name is called SLA

IF {F_TASKS.TA_STATUS}in["ACTIVE","ASSIGNED"]

AND {SLA_Task_Performance.TaskPerfSLAFixDate}  > CurrentDateTime

THEN 'SAFE OPEN'

ELSE

IF {F_TASKS.TA_STATUS}in["ACTIVE","ASSIGNED"]

AND {SLA_Task_Performance.TaskPerfSLAFixDate}  <=  CurrentDateTime

THEN 'FAILED OPEN'

ELSE

IF {F_TASKS.TA_STATUS}IN["COMPLETE","HISTORY","CANCELLED"]

AND ({SLA_Task_Performance.TaskPerfFixDate} <=

{SLA_Task_Performance.TaskPerfSLAFixDate})

OR ISNULL({SLA_Task_Performance.TaskPerfFixDate})

THEN 'SAFE CLOSED'

ELSE

'FAILED CLOSED'

After putting SLA to crosstab header, counts for each categories are shown depending on what category it is. However, I only want to show SAFE CLOSED.

I did try to use specified SAFE CLOSED from the grouping option and disregard others, to get its percentage. However it doesn't get the exact percentage of only SAFE CLOSED. as it only gets the 100%.

Can anyone help me to get the exact percentage of only SAFE CLOSED?

Many Thanks