Nowadays, most young people in cities choose housing loans to buy houses, get married and have children. We should consider the appropriate proportion of this expenditure to family income. Mainly from the dynamic point of view, to measure the average level. According to an ordinary family, there are two young people and four parents. When buying a house, the family income is I, assuming 1 10,000 yuan. When the repayment ratio is k, the disposable income is I( 1-k). Taking 1 10,000 yuan as an example, according to official data, China's savings rate is as high as 46%. However, as the real estate heats up, this number will drop. We will calculate it according to 40%, which should be the proportion of disposable income, excluding the income from real estate expenditure. In this way, the monthly savings is I( 1-k)*0.4, and the average household loan term is 15 years, and the equal cost method is adopted. And they are all for the wedding room. The average age is 7 years old, and she gave birth to a child two years later. Two years later, due to the birth of the child, and the expenses of the child need to reach 30% of the disposable income of the family, since then, the monthly savings have only been me (1-k)*0. 1. Suppose that after 10 years of marriage, parents may need a lot of money for physical reasons. You can look at the cash flow balance at this time first. At the same time, it is assumed that the household income will increase by 10% every five years. Over the past two years, I (1-k) * 0.4 * 242-5 years, and I (1-k) * 0.1* 365-10 years,1.50000.00000000606 Therefore, assuming that it needs 65438+ ten thousand yuan1-119.8 = 0.49, the loan amount should not exceed this figure, which is consistent with the current popular view. Look at low-income families, with a monthly income of 6000. Due to the rigidity of basic daily necessities, their own savings rate is only 20%, which drops to 8% after having children. After 10 years, it will be I (1-k) * 0.2 * 24+I (1-k) * 0.08 * 24+1.1* I (1* I). The balance is only 36 thousand, and I'm afraid there will be a big problem at this time Maybe many parents will have a balance, but many have already paid the down payment for buying a house. Unless my parents' old house is still there. As far as I know, there are many cases similar to the latter in Shanghai, which will expose serious social problems at some point.