Browsing the t'interweb it appears that most cars will lose up to 70% of their value after 5 years. Seems that Morgans are no different these days, perhaps a little better than average, but not much.

1972 4/4 4 seater, 1981 MGB GT
1984 Harley Davidson Electra Glide, 1990 Kawasaki ZX10