Hello. Good question. It’s explained somewhere in the site, but I can’t remember where. Here, most Kulaks are classified under “Peasants.” The only way to present these kinds of demographics meaningfully is to avoid double-counting. Somewhat meticulously, the 300,000 kulaks listed as dead, are separated and subtracted from the overall number of peasants.The shortcoming is acknowledged within the site and explained when discussing methodology. Your question is one of the primary reasons that this is a teaching tool and not a research tool. Great question though.
Or as dissidents I suppose. Still, the numbers look a little small. There should be at least 25 million Soviet victims of communism.