# Mean Time Between Failure

Hi all,

I want to calculate per year the Mean Time Between Failure.
We record failure in jira with the issue type incidents.
I want that per year this is calculated:

for the past years: 365*24/(number of incidents)
for the current year: days since start of year *24 / (number of incidents)

Can somebode help me at this topic?
BR, Herbert

Hi @HeWe!

It is possible to count how many days are in the year with DateDiffDays function and by using StartDate and NextStartDate:

For the current year, I count days until today. Here is the formula I used:

``````CASE WHEN DateInPeriod(Now(), [Time].CurrentHierarchyMember)
THEN
DateDiffDays([Time].[Year].CurrentDateMember.StartDate, DateWithoutTime(Now()))
ELSE DateDiffDays([Time].CurrentMember.StartDate, [Time].CurrentMember.NextStartDate)
END
``````

Further, in this formula, you can add the multiplication with 24 and division with the incident count.

Let me know if this works as expected for you!
Lauma / support@eazybi.com

That is exactly what i needed…Thanks for this great support.
We are using eaziBy more and more and are always supprized what is actually working or possible.

The biggest problem is the usage of cubes, how they work and how to formulate calculated member. Do you know if there is any training from eazyBi?

BR, Herbert

Hi @HeWe!

I’m happy to hear that you got the report you were looking for!

Yes, eazyBI data analysis capabilities are extensive. It does take some time, though, to grasp the multi-dimensional cube and the MDX scripting language. Some pointers to dig deeper:

Lauma / support@eazybi.com