"It may help us to understand what the World War really cost in lives and property if we think of it in terms of things we know.
If some great catastrophe had wiped out the total revenue of the United Kingdom for, say, the year 1909, the money loss would have been 300 times less than the direct cost of the war, that is, the expenditure for carrying on military operations. If we add the indirect costs - the economic loss from death and injury, loss of production, and property loss - the cost of the war is nearly doubled, reaching the staggering total of £67,000,000,000.
"If the entire population of England and Wales in 1831 - 13,000,000 - had been destroyed, the loss of life would have been no greater than that among the soldiers and sailors who fought in the World War.
"If the army of men who were wounded one or more times or taken prisoner had been drawn from England and Wales alone in 1914, it would have taken more than half the entire population. It is only by such comparisons that we can realise what the war really cost"
Source: "The Children's Encyclopaedia" (1920)