That's about 30% depreciation over 30mths. A report for news.motors.co.uk reckons "in the first year, a new car will typically depreciate 10-40%, losing value the very moment it’s driven off the dealer’s forecourt. By three years, that same new car, driving an average of 10,000 miles per year, could have lost as much as 60% of its value."
The old 'years long' waiting list has now gone, and coupled with the fact that their are so many options available it would be tricky to find someone who matches your ideas of colour and spec - this means they sit around on the sales forecourt for rather a long time.
Still, as you say, keeping your Mog can only be a good thing
"Y mae dafad ddu ym mhob praidd" 1972 4/4, 1981 MGBGT, 1984 FLHT1340, 1980 XLH1000, 1990 ZX10