Book Image

Extreme DAX

By : Michiel Rozema, Henk Vlootman
Book Image

Extreme DAX

By: Michiel Rozema, Henk Vlootman

Overview of this book

This book helps business analysts generate powerful and sophisticated analyses from their data using DAX and get the most out of Microsoft Business Intelligence tools. Extreme DAX will first teach you the principles of business intelligence, good model design, and how DAX fits into it all. Then, you’ll launch into detailed examples of DAX in real-world business scenarios such as inventory calculations, forecasting, intercompany business, and data security. At each step, senior DAX experts will walk you through the subtleties involved in working with Power BI models and common mistakes to look out for as you build advanced data aggregations. You’ll deepen your understanding of DAX functions, filters, and measures, and how and when they can be used to derive effective insights. You’ll also be provided with PBIX files for each chapter, so that you can follow along and explore in your own time.
Table of Contents (17 chapters)
Free Chapter
1
Part I: Introduction
6
Part II: Business cases
15
Other Books You May Enjoy
16
Index

Calculating Net Present Value (NPV)

The NPV is the sum of the present values of all cash flows over the years. Remember the definition of PV:

So, to calculate the PV of a cash flow in year n, we need to take the discount rate and divide the FV by a power of the discount rate. As an example, if you wanted to create a calculated column in the Property table with the PV of the residual value of each property (we are sure you don't want to do that by now!), you could do that with the formula below:

PV Residual Value =
VAR EndYearNr = 
    LOOKUPVALUE('Year'[YearNr], 'Year'[Year], Property[End Year])
VAR DiscountFactor =
    (1 + [Discount value]) ^ EndYearNr
RETURN
DIVIDE(Property[Residual Value], DiscountFactor)

In normal language: we take the property's end year, find the corresponding year number, calculate the discount factor with the year number as power, and divide the residual value by the discount factor. The discount factor is 1...