How to create a master item representing a moving difference?

[jleefjcapital]

Hello, 

I'm working with a series where the data are available in growth rates.  I would like to create a separate series showing the difference over the prior period.  Is there a straightforward way to do this? 

Thanks, 

Jes 

[Wlad_Masi]

Do you mind showing us a couple of lines of your data and the expected result?