Error message of GMM

[SKlim]

Dear All
I am using Eviews 7 and i got the error message of "Number of instruments greater than number of observations" from running GMM. The data is stacked by cross section. It is quarterly time series data (420 observations: 70 sample size for 6 countries). I run following regression over 6 countries.

GDP = C + one lag of GDP + Excess market return + dividend yield + standard deviation, National liquidity + global liquidity.

I use the dynamic wizard as following
1. dependent variable is GDP with one lag,
2. specify regressors are Excess market return, dividend yield, standard deviation, National liquidity, global liquidity, not including period dymmy,
3. tick Orthogonal deviations (because all variables are already orthogonalized)
4. @dyn(GDPT,-1)
5. Excess market return, dividend yield, standard deviation, national liquidity, global liquidity in the section of Transform (orthogonal deviations).
6. select 2-step and white period

I have got the error message " Number of instruments grater than number of observations" as i run the GMM. Also i tried to increase and decrease the number of instruments but i always get the error message.
I do not have any idea to solve this problem. Please help me out.

[EViews Gareth]

You need more observations (per cross-section) or fewer instruments.