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shocks

shocks;
 Command
SHOCK STATEMENT
[SHOCK STATEMENT]
...
end;

In deterministic context:
SHOCK STATEMENT:
var VARIABLE NAME;
periods PERIOD STATEMENT;
values VALUE STATEMENT;

PERIOD STATEMENT: NUMBER[:NUMBER] or LIST OF NUMBERS
VALUE STATEMENT: EXPRESSION

The VALUE STATEMENT must be a valid expression returning a scalar value or a vector when the shock applies to a range of periods and takes a different values in each of these periods.

For deterministic simulations, the shocks block specifies temporary changes in the value of an exogenous variables. For permanent shocks, use an endval block.

Example 

shocks;
var e;
periods 1;
values 0.5;
var u;
periods 4:5;
values 0;
end;

In stochastic context, syntax 1:
SHOCK STATEMENT:
var VARIABLE NAME[,VARIABLE NAME] = expression ;

For stochastic simulations (available only in the MATLAB or SCILAB versions), the shocks block specifies the non zero elements of the covariance matrix of the shocks.

Example 

shocks;
var e = 0.000081;
var e,u = phi*0.009*0.009;
var u = 0.000081;
end;

In stochastic context, syntax 2:
SHOCK STATEMENT:
var VARIABLE NAME;
stderr expression;

Alternatively, when the shocks are uncorrelated, it is possible to specify only the standard errors with a slightly different syntax (for consistency with previous versions).

Example 

shocks;
var e;
stderr 0.009;
var u;
stderr 0.009;
end;