In 1975, LEGO released 6 Building Set with People sets, all of these sets have been retired. For that year, the total price of all retail sets cost $22, today those sets are valued around $833, a growth of 3835%.
Most valuable 1975 Building Set with People set
190 Farm Set $385.86
Theme Building Set with People
Year 1975
Pieces 526
Availability Retired
190 LEGO Farm Set
Retail $7.49
Value $385.86
Growth  5051.7%
Annual growth 8.4%
Theme Building Set with People
Year 1975
Pieces 89
Availability Retired
195 LEGO Airplane
Retail $5.49
Value $100.69
Growth  1734.1%
Annual growth 5.3%
Theme Building Set with People
Year 1975
Pieces 1
Availability Retired
253-2 LEGO Helicopter and Pilot
Retail $1.49
Value $72.46
Growth  4763.1%
Annual growth 5.1%
Theme Building Set with People
Year 1975
Pieces 103
Availability Retired
254 LEGO Family
Retail $1.99
Value $84.98
Growth  4170.4%
Annual growth 8.0%
Theme Building Set with People
Year 1975
Pieces 120
Availability Retired
255-2 LEGO Farming Scene
Retail $2.29
Value $96.43
Growth  4110.9%
Annual growth 8.4%
Theme Building Set with People
Year 1975
Pieces 93
Availability Retired
814-2 LEGO Tractor
Retail $2.98
Value $92.87
Growth  3016.4%
Annual growth 7.3%