Hello everyone

If I have the gdp expressed in logarithms, that is, lgdp= 100*ln(gdp), then if I apply the one side hp filter, as Professor Johannes suggests, the units that I get directly from applying the hp filter to lgdp are percentage (deviation from trend) right?

Now, if I have the annualized inflation (\Pi) and I directly apply the hp filter to \Pi, is the cyclic variable that I get also in percentage?

Thanks in advance