The qT is the ratio of collected transaction fee to the average balance in time length T. By year 2016 data about USA, the M1 is 3350 billion and the population is 323.4 million so the balance per capita is USD 10359. Assuming a 0.05 USD transaction fee for 2~3 transactions a day, then in one year 31536000 seconds the ratio qT is therefore 0.003524~0.005285. More educative guess shall be developed in the future.

Think in the energy-based money mindset. Denote

• K the energy power devoted to money in the society
• W the average energy power for all consuming energy economy activity in the society
• V the money volume
• P the money's price, its proof-of-work
• T the time length for the money to be exhausted, therefore T=VP/W

Then

K/W = qVP/W = qT

Should T and K and W be known, the estimation can be done as well. "trust" as a commodity specific for social cooperation needs, the producers of the trust shall know K. If everyone lives alone in a self-sustained homestead way, then people need no money as T and K and V are zero. Wealth is defined by the possession of energy for consumption, not necessarily the same as the possession of money.

Another approach to estimate q or q' is by way of loss of moving energy accross time, a quantitative theory is explained here in MacroEconomicsTheory.