Pivot table with value based in another value

[#1]

Hello,

I have some values by week.

I want to show the week and two columns, one with the value of the week and another that shows the value of the week+2.

Ex.

Data

Week   WeekValue  

1               10

2               20   

3               30

4               40

5               50

6               60

I want to create a pivot table that includes a column that shows the value of the week+2. The result should be:

Week   WeekValue   NewColumn = Week +2

1               10            30                    Value of Week3

2               20            40                    Value of Week4

3               30            50                    Value of Week5    

4               40            60                    Value of Week6

5               50             ...

6               60             ...

...              ...              ...

Thanks in advance for your help.

[Gysbert_Wassenaar]

If the expression for WeekValue is sum(WeekValue) then the expression for NewColumn is below(sum(WeekValue),2,1)

[#3]

Hello, The problem is that I have another dimension, I can't get the value by position.

Check my table below.

I have exchange rates by Year, Week and Currency. I'm showing the avg of the Exchange Rate by week and in the last column I want to show the avg for the week +12.