In the twentieth century, Russia has suffered a series of social cataclysms. The demographic crises which have followed have had disastrous implications. They occurred in 1915-1921, 1928-1934, and 1941-1947. According to our lowest estimate, these three crises lasting 6 years each and 7 years apart have accounted for a loss of 38 million people, including losses due to the deficit in births, excess of deaths, and emigration.

Теперь от 38 млн. нужно отнять демографические потери на первую мировую, гражданскую и ВОВ (с учетом нерожденных и эмигрантoв), и получатся потери на репрессии и колективизацию.