Not long ago I actually did some calculations on the appreciation in value of my particular collection over the past 20 years. I used my purchase prices, then estimated current values, then calculated the increase in value if it were in compounding annual percent yield for each machine. Turns out it was just about an average 4-5% a year for the past 20 years. Inflation has been running really low like what, 1% a year? So there you can get a sense for how much is inflation vs pinflation.

Update: looks like pinflation has been a little higher since I did this a couple years ago. For example I bought a players cond funhouse 20 years ago for $1200 and if that can go for 4-5k today that’s like 6-7% apy