Writing variable in Dynare

Hi
I would like to ask question about writing variable in Dynare . In my model (optimal fiscal policy under commodity price shock) I have one equation (sovereign fund ) about law of motion for stock of asset Ft+1=Ft+Tt
Where Ft+1 is stock of asset in t+1 time and Ft is stock of asset in t time and Tt is oil revenue in time t . It means country put oil revenue which it earns in time t in sovereign fund and then stock of asset accumulation rule is set as above.

I would like to ask when I write this equation I should write Ft+1 variable as a F (not F(+1)) which is like writing capital .

Thanks from now
Sincerely yours.

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Yes, that variable is a predetermined variable and needs to be entered as such, i.e.

F=F(-1)+T

Alternatively, you can use the predetermined_variables-command.

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Thanks so much Dear Johannes Pfeifer.

Sorry that I took your valuable time. As similar I have one equation which I forgot to add previous message.
Dt+1=(1+rt)Dt+Gt-Tt
which is government’s flow budget constraint where

Dt is goverment debt in time t; rt is interest rate in time t; Gt is goverment spending in time t ; Tt is tax revenue in time t.
I would like to ask when I write this equation I should write Dt+1 variable as a D (not D(+1)) which is like writing capital or D is not predetermined variable here.
Thanks for your help and patience. Your help is very important for me.
Sincerely yours

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The same applies here. Stocks like this are (almost) always predetermined variables.

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what is the subscript of r in the above equation(Dt+1=(1+rt)Dt+Gt-Tt)?
r(t) or r(t-1)?
generally, when we describe an asset in the model that is predetermined variable, we should put t-1 as subscript. but what is the subscript of return of asset?
for exp. subscript of return of capital in the household budget constraint?
subscript of return of bond in the household budget constraint and government budget constraint?

That depends on the setup. If the return is known in advance, it gets timing (-1). If its determined at time t, because e.g. a stochastic shock first needs to realize, it gets timing t. Stock returns for example usually depend on TFP at time t and are therefore non-predetermined, while the nominal return on bonds is agreed upon in advance and is therefore predetermined. In contrast, the real return on bonds depends on the realization of inflation at time t and is therefore not predetermined.