generating series with if condition

[Eppichgyo]

Hi,

I want to create 'previous dec=100' index. I create in Excel a dummy series with value 1 if month=January else 0.

My code:

if dummy=1 then
prev_dec=cpi/cpi(-1)*100
else
prev_dec=prev_dec(-1)*(cpi/cpi(-1))
endif

but it does not work

[EViews Gareth]

http://forums.eviews.com/viewtopic.php?f=5&t=3765

[Eppichgyo]

http://forums.eviews.com/viewtopic.php?f=5&t=3765

Thanks Gareth