Good Job
Lr = k(Y*X)
X = |(S-B)/B|
I agree with you that you need to find the X factor to measure change. Is this equation with correct results?
The absolute value of measuring the difference in value between two values divided by one of the two values is a measure that may lead to false results, although approaching the true value will be closer.
Try some charts to compare the willingness to pay in BTC and the price change.
In my previous analysis, I took the function without modulus and my point was explicitly based on the fact that if price on the day of expenditure is lower than the price on the day of income, people will tend to hold money rather than spending it. But later I found out that it works both ways. Let say if that value of Bitcoin unexpectedly rises on the day of expenditure, people may tend to hold bitcoins rather than spending them. Hence higher the value of X, more btc will be held. On the contrary, closer the value of X to 0, lesser will be the impact of X on people's tendency to hold bitcoins.
Do not forget that there are some effects where I can pay now if I expect a decline in independently or bad events.
Yeah, this may be an addition to above said equation in the form of another variable.
As you said, it will be better if I present this in the form of graph. I will make one in next day or two in my free time with more detailed study.