Am 28.10.2022 um 16:42 schrieb Lars Ahnland:
 Hi,
 Sorry, I used the two variables Debt_ratio and Capital_share, with a 
 restriced contant model. The lag length, according to a majority of 
 information criteria, is 2.
 
OK, I tried your first subsample (BTW, I found it quite nice how gretl 
directly imported the series from the xlsx file without a hiccup...), 
and I also get a p-value below 5%. Remember, however, that this just 
means that the test finds one stationary component ( = "direction") in 
the system. By eyeballing that series I would bet that the capital share 
is an I(0) variable, at least in the perspective of this subsample. So 
yes, I'd say that the result is reliable, but it may not mean what you 
were expecting.
cheers
sven