interpretation benefit (i,j) state. usefullly
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Figure A1.2 Change In consumers'surplus notionally, to take tl:e conventional form of a backwardsloping demand curve. It is customary to look at the change in consumers' surplus for a change in costs. Then the shaded area above the line of travel cost c(~) can be interpreted as con-lJ sumers' surplus in an obvious way: those consumers were prepared to pay more (and an amount given by that area) but do not have to. If the travel cost is reduced to c(~), then thelJ diagonally-shaded area represents the change in consumers' surplus.