variable using previous year data

[elliask]

Hello, I apologize for the confusing title as I really don't know how to describe the problem and I'm not a native english speaker, so this is the best I can come up with.
I have a question regarding analysis using 30 years time series data and this equation : Yt = Ct-1 + rt + EXt + Gt + KGDPt
In the equation Ct-1 = consumption data from previous year, my question is how can I input the data to the equation and run the analysis? Do I need to input 31 years data or input the Ct-1 data separately or is there any specific command to do that?
I appreciate any help and feedback, thank you.

[EViews Gareth]

Assuming you have annual data, enter the variable as consumption(-1)

[elliask]

Thanks for replying.
If it's not bother can you elaborate this in more detail as I'm really new to eviews and all. And since i have to put -1 does it means that i need 31 years data, lets just say i need to analyze 1988-2017 so I need data from 1987-2017. This really confuses me because when you start workfile you have to decide the lenght of the analysis.

[EViews Gareth]

Create the workfile with however much data you have. EViews will figure out how much it can use during estimation itself.