The Trek 1200 goes for about $1000 new (Canadian dollars) where I live. The ad doesn't say how old it is.
When my husband sold his three year old 'cross bike, he was advised to ask about 60% of what he'd paid new. If he'd kept it another year, he could have asked about 50%, so perhaps -10% per year? (Up to a point, of course. As nice as it would be to get a negative price, a bike has to be really decrepit before the seller is paying you to take it away.
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