"That's odd," said Vector, peering at the sketch she'd just made of the number of Muggleborns in any given incoming class graphed on the same scale as the total number of incoming students. She'd been expecting a correlation, from which she might deduce the average number of Muggleborns over a large span of time, but the two curves did not seem to vary especially dependently. She'd tried putting in vertical dotted lines for the beginning and end of the War, and after some consideration also the previous European war.