Minimum Number of Observations VAR

[tonidastier]

Hi everybody,

I need to analyse the relation between the inventory/sales-ratio and the z-score via a VAR, and to test for Granger Causality afterwards.
I only have annual data from 1989 to 2005, i.e. 15 observations.
Is this number of observations enough for providing valid results?
I am quite insecure!

Thanks a lot for your help,

Andi