businesses with the highest profit margins Under the theoretical framework of the theory, the theory of commodity market equilibrium and the monetary market equilibrium of Keynesian theory are unified. Marx's theory of interest rate decisions from the perspective of the source and essence of interest, taking into account the institutional factors in the role of interest rate decisions of interest theory, its theoretical core is the interest rate is determined by the average profit margin. Marx believed that under capitalism, interest is a part of profit and a form of conversion of surplus value. Ford motor co., in 1915, produced a car that was different from a horse model In January, Ikano's top account paid 2.05 PC, while Secure Trust Bank now pays 2.51 PC. Michael Zezas, an analyst at Morgan Stanley, also said the tax legislation would be a boon to the market in the short term, but may not be able to make fundamental changes. The current flattening of the us Treasury yield curve shows that the medium-term slowdown in the us economy and the recession of 2019 are not going away. A tax reform would widen the fiscal deficit, possibly in the future and exacerbate cyclical risks in the economy. Above all, they can avoid meddling in parliamentary politics, as the ECB did when Italy's silvio berlusconi government collapsed in 2011. Then they can lower their heads and hope for the best.