(1) Questions raised

In academic circles, Chinese and foreign scholars have been paying close attention to the effect of financing governance, and the earliest research can be traced back to MM theorem. At that time, a series of assumptions were put forward, and the final conclusion was that there was no correlation between financing structure and enterprise value. But through later assumptions, it is contrary to this result. Later, scholars further studied, relaxed the assumptions, introduced other factors such as corporate income tax, personal income tax and bankruptcy cost, and then got some new theories. Financing is very important for enterprises. Reasonable financing can reduce the financing cost of enterprises, in addition, it is also a method and strategy to increase enterprise value. Because of this, how much is the optimal capital structure to maximize the enterprise's value and how to adjust the financing structure is an unavoidable strategic issue for enterprises, and it is also a problem that enterprises must consider when making financing decisions.

(2) Definition of related concepts

1. Debt structure

The debt structure in this paper includes not only the proportion of total debt, but also the term structure and type structure of debt itself.

The author thinks that the asset-liability ratio can better reflect the proportion of corporate debt to total capital, so the asset-liability ratio is adopted to reflect the level of corporate total debt structure.

In the term structure of liabilities, it is generally divided by time. In this paper, the long-term debt ratio is reflected by the ratio of liabilities to total liabilities for more than one year at the end of the period, and the short-term debt ratio is reflected by the ratio of current liabilities to total liabilities.

In China, the liabilities of enterprises generally come from bank loans, that is, bank loans; Commercial credits such as accounts payable and accounts received in advance formed in the course of daily operations; The other is bonds issued by enterprises, namely bonds payable. However, due to the slow development of China's bond market and the small proportion of corporate bond financing, this paper mainly examines the first two types of liabilities.

2. Enterprise value and enterprise value evaluation

In practice, enterprise value can be divided into intrinsic value and market value. Generally speaking, the market value consists of the market value of the company's shares and the market value of the company's bonds. Intrinsic value refers to the real economic value of an enterprise, which is the value of the enterprise itself. Information asymmetry, according to the market law, the market value of enterprises always fluctuates up and down the intrinsic value.

Enterprise value evaluation refers to the comprehensive evaluation of the overall asset value of the enterprise according to the current and future profitability of the enterprise and fully considering various influencing factors.

Because the enterprise is regarded as a whole, including tangible assets and intangible assets, it is also called overall asset evaluation. However, the evaluation process is not the accumulation of individual asset evaluation values, but an abstract organic combination is formed according to a certain abstract logical relationship between organizational management and science. With the development of technology, there are more and more evaluation methods. Of course, it is important to choose which evaluation method, because the enterprise value calculated by different methods is very different. At present, the representative evaluation methods are historical cost method, present value method of income, option evaluation method and market method. The method system is shown in figure 1.

In this paper, Tobin Q, which is commonly used in academic circles, is selected as a measure of enterprise value. In order to make its value more truly reflect the situation of listed companies in China, this paper makes some adjustments in combination with China's reality.

Because there are two kinds of shares of listed companies in China: tradable shares and non-tradable shares. Among them, non-tradable shares are divided into state-owned shares and legal person shares. At the end of 2004, some non-tradable shares began to be gradually transformed into tradable shares under certain conditions. In the process of transformation, the pricing principle of non-tradable shares is generally based on the net assets per share of listed companies, so this paper also uses net assets per share to replace the market price of non-tradable shares when calculating Tobin Q. For the convenience of calculation, the stock price of tradable shares takes the price of the last trading day of each year.

Second, the empirical analysis of the relationship between enterprise value and financing structure

Sample selection

This paper takes the listed manufacturing companies as the research object, and selects the data from 2005 to 2007 to analyze the relationship between financing structure and enterprise value. The data here comes from the national Taian database. For the rigor of the study, the data were screened from two aspects: First, st and PT companies were excluded. These companies are in an abnormal state, or losing money continuously. If we study them at the same time, it will affect the empirical conclusion. The second is to exclude companies that have been listed for less than two years, because the newly listed companies have not yet entered the normal business track and have packaging components.

(II) Definition of variables (see table 1)

Because of the scale of the enterprise, the value of the enterprise is also related to different enterprise scales; In addition, enterprise growth opportunities will also affect enterprise value, so this paper selects enterprise scale and enterprise growth opportunities as control variables, and uses the logarithm of total assets to represent enterprise scale and the growth rate of total assets to represent enterprise growth opportunities.

(3) research hypothesis

Suppose 1: the enterprise value first increases with the increase of asset-liability ratio, and then decreases with the increase of asset-liability ratio after a certain point, and there is an optimal value.

From the perspective of trade-off theory, debt financing has advantages and disadvantages. On the one hand, the utility of interest tax deduction: compared with equity financing, the main advantage of debt is that it can bring tax benefits to enterprises, that is, the interest of debt can be deducted from pre-tax profits, which correspondingly reduces net profit, and enterprises pay less taxes, reduce cost outflow and increase enterprise value; The utility of financial leverage, creditors generally only require enterprises to pay a certain amount of interest regularly, and will not pay dividends on operating results. When the profit obtained by the enterprise from the operation of funds integrated with liabilities far exceeds the interest to be paid, the rest will be owned by shareholders, which improves the performance of the enterprise, that is, the financial leverage effect of liabilities; Debt can reduce conflicts between managers and shareholders. With the involvement of external shareholders, managers will find that the addition of an interest group-shareholders' meeting will cause conflicts of interest, but debt financing will closely link the interests of managers and shareholders, thus effectively reducing the agency conflict between them. On the other hand, if the asset-liability ratio is too high, it will lead to financial crisis. The pressure of repaying principal and interest brings certain problems to the operation of enterprises, especially when the operation is not good, the profit does not cover the interest, which is prone to financial crisis; Excessive debt financing needs to pay too much interest, leading to conflicts of interest. In addition, there are also differences between creditors and equity holders in the use of funds. Shareholders prefer high-risk and high-yield projects, while creditors generally prefer prudent investment projects. Therefore, the relationship between debt financing and enterprise value is not a single linear relationship, and too high or too low is not conducive to the development of enterprises. Enterprise value first increases with the increase of asset-liability ratio, and then decreases with the increase of asset-liability ratio after reaching a certain value, and there is an optimal value.

Hypothesis 2: The short-term debt financing ratio of enterprises is positively related to enterprise value; The proportion of long-term debt financing is negatively correlated with enterprise value.

Short-term loans are loans that enterprises borrow from financial institutions or non-financial institutions other than themselves within 1 year. In the modern market economy, with the development of capital market and various financing tools, short-term debt funds have more advantages such as convertibility, flexibility and diversity, which is more conducive to adjusting the capital structure of enterprises. On the one hand, the funds raised by short-term liabilities can make up for the lack of investment; On the other hand, it can also curb excessive investment, which is more conducive to the governance effect of enterprises. Long-term liabilities generally refer to loans with a time exceeding 1 year, and loans due within one year are generally classified as short-term loans. Compared with short-term liabilities, long-term liabilities have the characteristics of larger amount and longer repayment period. In addition, compared with short-term loans, long-term loans take a long time and the transformation is not flexible, so it is difficult to restrain enterprises. For example, due to the long repayment time, enterprises will first consider misappropriating long-term loans instead of short-term loans in special circumstances. Therefore, short-term borrowing plays a better supervisory role than long-term borrowing in supervising the use of enterprise funds, so it is proposed that the proportion of short-term debt financing is positively related to enterprise value; The proportion of long-term debt financing is negatively correlated with enterprise value.

Hypothesis 3: Commercial credit is negatively correlated with enterprise value, while bank loans are positively correlated with enterprise value.

Commercial credit is a common credit relationship between enterprises due to deferred payment or early payment in normal business activities and commodity transactions. In essence, commercial credit is based on the honesty and credit of both parties, and both parties promise to be responsible for their respective obligations. Subjectively speaking, honesty means that in trading activities, both parties to the transaction should be honest and trustworthy in concept, and there are no other malicious and ulterior motives except sincere and fair transactions between the two parties; Objectively, we should fulfill our commitments and fulfill our contractual and agreement obligations. From the definition of commercial credit, the advantages are: normal production and business activities can be formed, and it can be raised quickly and timely. For example, an enterprise is about to pay an account for raw materials, but other aspects of the enterprise are in urgent need of this fund, so delaying the payment of raw materials will form commercial credit. Its disadvantages are: commercial credit is naturally formed on the basis of credit, and there is no specific loan procedure, such as pledge; Secondly, it is not clear whether enterprises really can't turn over funds or use credit for other purposes. The worst plan is that enterprises get into trouble and fail to fulfill their responsibilities, so they can only take legal weapons to safeguard their own interests. Therefore, commercial credit has a poor performance on corporate governance and has a certain negative effect on the value of enterprises.

Bank loan refers to a financing method in which an enterprise borrows the required funds from relevant banks or non-bank financial institutions according to the loan contract, also known as bank loan financing. Banks have specialized loan departments and specialized professionals. In order to reduce the bad debt rate, the procedures for each loan are more complicated. The first is the credit investigation before the loan, to investigate whether the lender has the ability to repay the debt; The second is to sign a series of contract agreements after approval to provide mortgage, pledge and guarantee. In addition, banks generally have the ability to intervene in corporate governance after lending. Relatively speaking, the bank loan policy is more cautious, and the pressure on enterprises is greater, which also promotes enterprises to use funds from various sources more effectively and reasonably. Therefore, it is proposed that commercial credit is negatively correlated with enterprise value, and bank loans are positively correlated with enterprise value.

Research mode

Referring to the method system of regression analysis, this paper establishes the following model when analyzing the relationship between financing structure and enterprise value:

Model 1: Test the relationship between the overall debt level and enterprise value.

q =α+β 1 lev+β2 size+β3 growth+ε

Model 2: Test the relationship between debt maturity structure and enterprise value. ①

q =α+β 1SD+β2 size+β3 growth+ε

q =α+β 1LD+β2 size+β3 growth+ε

Model 3: Test the relationship between debt type structure and enterprise value.

q =α+β 1BD+β2CD+β3 size+β4 growth+ε

Note: α, β and ε in the above formula are constant terms, coefficient terms and error terms of related variables respectively.

(v) Analysis of empirical research results

In this paper, the relationship between financing structure and enterprise value is empirically tested by SPSS statistical analysis, and the regression results are analyzed according to the above model.

1. Regression analysis of asset-liability ratio and enterprise value