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 $2,943, a growth of 4107%.
Most valuable 1978 LEGO Trains set
165 Cargo Station $2,083.23
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 $407.68
Growth  +8069.9%
Annual growth 9.6%

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 $2,083.23
Growth  +13797.5%
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 $262.27
Growth  +993.2%
Annual growth 3.0%

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 $190.06
Growth  +631.3%
Annual growth 4.2%