Hmm, I think it has to be operating earnings (EBIT) because including depreciation and amortization does make little sense and S&P is also using operating earnings.
I think as well that the difference being attributable to interest expenses makes a lot of sense.
Overall I think we should continuously build defitions in the Wiki and link to it so that certain differentiations become way easier for the reader when reading a post like this.
When researching the topic I found this article interesting. It talks about a 3% Russel 2024 EPS growth estimate consensus and shows that EPS targets for small caps have been consistently revised downwards. It also mentions that more than 40% of Russell 2000 companies are unprofitable. (You talked about here as well) and has a longer report attached to it. Those reports should always be interesting for us, first in order to see if they have good elements and second because we want to start collecting them (maybe in Miro) in preparation to eventually creating our own more condensed reports.