Help to customize table using existing data and calculations

Dear Power BI 🙂

I have the following data table I need to convert into a new table:

So essentially, I receive values for cars at given ages: Newbuild, 5, 10 and 15 years old. 
From that data I need to make a table that show the value of a car at any given age. I need to fill in the values between newbuild and 5 year old and 10 years old etc. The way the numbers need to be filled in is by a linear depreciation. So if a Ford newbuild is worth 45 and a 5 years old Ford is worth 40, then the car have decreased by 5 over 5 years and thus 1 over 1 year. I think I have made the calculations clear in the picture. 

My problem is that I have no Idea to make such a table in Power BI. The picture is from Excel, where this seems to be easy to do. 

Can anyone help me?

Sincerely, Signe