Dear Anton,

As per my understanding , first you need to calculate the weekdays i,e you need to exclude the weekends . And once you get the no of weekdays then you can convert those days into working hours.I am not sure weather it will solve your problem fully or not but at least it will give you a start .

Calculate the Number of Business Days Between Two Dates

Follow the steps below to calculate the number of business days between two dates using a calculated field. Download and open the Calculate Business Days Two Dates workbook to follow the steps below.

Step 1

In Tableau Desktop, select Analysis > Create Calculated Field.

Step 2

In the Calculated Field dialog box that opens, enter a name for the field.

In the formula field, type the following, and then click OK:

DATEDIFF('week',[<Start Date>],[<End Date>])*5

+

MIN(DATEPART('weekday',[<End Date>]),6)

-

MIN(DATEPART('weekday',[<Start Date>]),6)

Where <Start Date> and <End Date> are the names of date fields in the worksheet.

Anton:

There was a post done sometime back around similar question. Check this out; How to Calculate Working Minutes- Excluding Weekends and Holidays

..kk