Principal is called present value in financial management, which means that a certain amount of cash at a certain point in the future is converted into present value. Principal refers to the funds advanced by various economic organizations and individuals for production and business activities.
2. Interest refers to the remuneration that money holders (creditors) get from borrowers (debtors) for lending money or monetary capital.
Including deposit interest, loan interest and interest generated by various bonds. Under the capitalist system, the source of interest is the surplus value created by hired workers. The essence of interest is a special transformation form of surplus value and a part of profit.
3. Interest rate refers to the ratio of interest amount to loan amount, that is, principal, in a certain period.
Interest rate is the main factor that determines the capital cost of enterprises, and it is also the decisive factor for enterprises to raise funds and invest. To study the financial environment, we must pay attention to the current situation and changing trend of interest rates.
Extended data:
Examples of principal, interest and interest rate conversion:
Ordinary residents generally adopt the method of lump sum deposit and lump sum withdrawal. Take the calculation of lump-sum deposit and withdrawal interest rate as an example.
The balance of lump-sum deposit and lump-sum withdrawal is increasing day by day, so interest cannot be simply calculated by lump-sum deposit and lump-sum withdrawal, and only simple interest annuity can be used. The formula is as follows:
SN = A（ 1+R）+A（ 1+2R）+？ +A（ 1+NR）
= NA+ 1/2n（N+ 1）AR
Among them, A represents the principal deposited in each period, SN is the sum of the principal and interest after N periods, and SN can also be called the final value of simple interest annuity. In the above formula, NA is the total amount of principal saved, and1/2n (n101) ar is the total amount of interest earned.
Usually deposit once a month, and the deposit amount is the same every time. Therefore, for convenience, we can change the deposit term to a constant, as shown below:
If the shelf life is 1 year, then d =1/2n (n101) =1/2x0/2x0 (12+1) = 78.
Similarly, if the storage period is 2 years, the constant can be calculated as D=300 by the above formula, and if the storage period is 3 years, the constant is D=666.
In this way, there is:1/2n (n1kloc-0/) ar = Dar, that is, zero deposit and lump sum interest.
For example, your monthly deposit is 1000 yuan. The term of deposit is 1 year, and the monthly interest rate of deposit is 1.425 ‰ (one-year lump-sum deposit and lump-sum withdrawal from October 29th, 2004 is the current monthly interest rate), so the annual interest at maturity is1000× 78×1.
Another example is the depositor's overdue withdrawal. Then, according to the current interest rate, calculate the interest of the overdue days of the due balance.
There is another method to calculate interest in lump sum deposit and withdrawal, that is, the fixed interest rate method.
The so-called fixed interest method is to use the product method to calculate the interest of each yuan into a fixed interest, and then multiply the fixed interest of each yuan by the balance due to get the interest amount.
The fixed interest per yuan = 1/2(N+ 1) NAR.
= 1/2（N ten 1）R
If, at present, the monthly interest in one-year installments is 1.425‰. Then, we can calculate the fixed interest per yuan as follows:1/2× (12+1)×1.425 ‰ = 0.0092625.
Your monthly deposit is 1000 yuan, and the balance due is:1000×12 =12000 yuan.
Then the interest is:12000× 0.0092625 =11.15 (yuan).
After deducting 20% interest tax of 22.23 yuan, the actual interest can be 88.92 yuan. (Note: Interest generated after June 65438+10/October 9, 2008 is not subject to interest tax. )
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