In the loss function version PolTajka the loss function comprises

four target variables: real gross domestic product growth, GDP price changes,
unemployment rate and balance of current account as a percentage of the
GDP in current prices.

Different policy constellations are contrived by changing the target values
and weights applied as coefficients when adding up the squared deviations
of the target variables from their target values.

One of the target value constellations is the latest Ministry of Finance
forecast.

Different weights are used for exceeding and remaining short of the target
values.
The value of the loss function is the following sum of squares:
X = instrument value supplied by the user
X_{0} = initial value of the instrument
Y = target value calculated by the model
Y_{0} = target value of the target variable
v = weight of instrument
w = weight of the target variable
