When measuring the price index of natural gas should you average in contracts written 50 years ago but still active, regardless of whether that price is currently available on the market?

> Eating food grown yourself is a different experience than shopping at the supermarket. Should we factor farm land cost into the CPI?

If 70% of the population paid for a "gardening experience" like they do for gym memberships, etc then yeah I would expect that to be in CPI.