In 1978, LEGO released 4 Trains sets in the subtheme 4512V, all of these sets have been retired. For that year, the total price of all retail sets cost $70, today those sets are valued around $2,850, a growth of 3973%.
Most valuable 1978 LEGO Trains set
165 Cargo Station $2,057.37
4 sets

164 Passenger Coach

Theme / Subtheme Trains / 4.5V / 12V
Year 1978
Pieces / Minifigs 148 / 2
Availability Retired
164 LEGO Trains Passenger Coach
Retail $4.99
Value $377.93
Growth  +7473.7%
Annual growth 6.1%

165 Cargo Station

Theme / Subtheme Trains / 4.5V / 12V
Year 1978
Pieces / Minifigs 268 / 2
Availability Retired
165 LEGO Trains Cargo Station
Retail $14.99
Value $2,057.37
Growth  +13624.9%
Annual growth 10.8%

166 Flat wagon

Theme / Subtheme Trains / 4.5V / 12V
Year 1978
Pieces / Minifigs 53 / 2
Availability Retired
166 LEGO Trains Flat wagon
Retail $23.99
Value $226.63
Growth  +844.7%
Annual growth 2.7%

167 Car Transport Wagon

Theme / Subtheme Trains / 4.5V / 12V
Year 1978
Pieces / Minifigs 102 / 2
Availability Retired
167 LEGO Trains Car Transport Wagon
Retail $25.99
Value $187.70
Growth  +622.2%
Annual growth 4.2%