In 1965, LEGO released 3 Classic Supplemental sets, all of these sets have been retired. For that year, the total price of all retail sets cost $2, today those sets are valued around $225, a growth of 14933%.
Most valuable 1965 LEGO Classic Supplemental set
509 38 Slimbricks Assorted Sizes $87.69
Largest 1965 LEGO Classic Supplemental set
510-2 Tiles 52 pieces
Most owned 1965 Classic Supplemental set
409 38 Slimbricks Assorted Sizes
3 sets

409 38 Slimbricks Assorted Sizes

Theme / Subtheme Classic / Supplemental
Year 1965
Pieces 38
Availability Retired
409 LEGO 38 Slimbricks Assorted Sizes
Retail $0.50
Value $78.97
Growth  +15694.0%
Annual growth 7.4%

509 38 Slimbricks Assorted Sizes

Theme / Subtheme Classic / Supplemental
Year 1965
Pieces 38
Availability Retired
509 LEGO 38 Slimbricks Assorted Sizes
Retail $0.50
Value $87.69
Growth  +17438.0%
Annual growth 7.6%

510-2 Tiles

Theme / Subtheme Classic / Supplemental
Year 1965
Pieces 52
Availability Retired
510-2 LEGO Tiles
Retail $0.50
Value $58.83
Growth  +11666.0%
Annual growth 6.9%