1, Friedman put forward the hypothesis of persistent income: the formula is Ct=b 1Yt+b2Yt- 1.

2. The relative income hypothesis is another person's (name forgotten) hypothesis. One theory holds that consumers' consumption expenditure is not only affected by current income, but also by past income and consumption level, especially in the past "peak period". The formula is completely different. At least there's a Ymax in it.

I don't know how you got the above formula. If you combine the above two points, can you explain the principle clearly, because according to your formula, consumption expenditure seems to have a certain number of time series, and it seems that it can be predicted according to the current period.