Assuming that the national debt is a stable income, then your income after one year is also stable. Under the same amount of funds, your futures income will be several times that of the spot, and the multiple is the margin ratio given to you by the exchange where you open an account.

It looks very profitable. The problem is that futures will fluctuate indefinitely during the year. The leverage brought by the margin will amplify the risk of your position, so you should increase the margin to prevent the position from exploding. In this way, these reserved funds will reduce the above profit ratio. How big these fluctuations will be and how much money you will reserve are unpredictable and will affect your income.

But in the spot, you can get 654.38+0 million, which is 654.38+0 million times a theoretical value.

This is a casual remark. If you really want to enter the market, I suggest you have some basic futures knowledge. You want to invest in futures, which is quite risky. Be careful.