People decorated trees with shiny ornaments at Christmas time.
It reflects events leading up to the Russian Revolution & then into the Stalinist era of the Soviet Union. He wrote the manuscript in 1943 and 1944 subsequent to his experiences during the Spanish Civil War.
Sorry if this is a bit confusing
I would say that it hasn't increased 20% because 1. if the starting percentage was 18%, you would see a larger precentage but that isn't the case.
I would help you out, if you had included the excerpt.