Forecasting not possible - missing data

[maca]

For our studies, we are supposed to model a stock regression. We came up with a model, which we assume is quite good and we were confident about our output.
The equation is
Stock C Rent3 GDP3 Empl3 Takeup4 Vac3 Int3

Our task is to forecast a period from 2012 to 2016. We only have full data of GDP, Employment and Takeup (Forecasts 2012-2016). Thus, we are missing the forecasts for Vacancy, Rent and Interest. Our actual data is from 1982 until 2011.
When computing the forecast in Eviews, an error message popped up saying "unable to compute due to missing data"
What can we do? Help, please! Attached you'll find our work and the excel sheet covering the dataset.

REMF_project_Option_B(2).xls

Excel Sheet with dataset

(60 KiB) Downloaded 301 times

LondonOffices.wf1

Eviews File for London Offices

(46.74 KiB) Downloaded 246 times

[maca]

THANK YOU,
MACA

[EViews Gareth]

You need data for those other variables.

[maca]

what do you mean? we can only use the data given....

[startz]

To make a forecast, it's necessary to multiply estimated coefficients by the right hand side variables. So either you need to confine yourself to variables that will be known in the future, or you need to find a way to forecast the right hand side variables before making the forecast for the left hand side variable.

Maybe that's what the assignment is trying to teach you?

[maca]

got it now.... thanks!