Sentence:  But poverty's scourge is fiercest below $1.25 (the average of the 15 poorest countries' own poverty lines, <WSD>measured</WSD> in 2005 dollars and adjusted for differences in purchasing power): people below that level live lives that are poor, nasty, brutish and short. 
Meaning of the word marked with <WSD> tags:  To ascertain the quantity of a unit of material via calculated comparison with respect to a standard.