29 Capital Structure

29.1 Meaning

Capital structure is the mix of long-term sources of finance — equity, preference, retained earnings and long-term debt — used by a firm. It is one of the firm’s strategic financial decisions because it changes both the cost and the risk attached to the firm’s earnings stream (pandey2021?; khan2022?; chandra2023?).

A wider concept — financial structure — covers the entire liability side: long-term capital plus current liabilities. Capital structure is the long-term part of financial structure.

Capital Structure vs Financial Structure

Dimension	Capital Structure	Financial Structure
Coverage	Long-term sources only	All sources, long-term + short-term
Components	Equity, preference, retained earnings, long-term debt	Capital structure + current liabilities
Strategic horizon	Long-term decision	Includes short-term financing too

29.2 Determinants of Capital Structure

Twelve Determinants of Capital Structure

Determinant	Working content
Cost of capital	Minimise WACC
Risk	Business risk and financial risk
Control	Equity dilutes control; debt does not
Flexibility	Future ability to raise more
Profitability and tax position	Tax shield on debt; benefit needs profits
Stability of earnings	Stable earnings can support more debt
Asset structure	Tangible assets support secured debt
Growth and life cycle stage	Start-ups → equity; mature → debt
Industry norms	Sectoral capital-structure averages
Market conditions	Investor sentiment, interest rate cycle
Legal and regulatory factors	Sectoral caps, prudential limits
Size of the firm	Larger firms have wider access

The optimum capital structure is the mix that minimises WACC and maximises firm value. Whether such an optimum exists is the central debate of capital-structure theory.

29.3 Theories of Capital Structure — A Map

Four foundational theories were developed in the 1950s; three behavioural / informational extensions came later.

flowchart TB
  CS[Capital Structure<br/>Theories] --> NI[Net Income Approach<br/>Durand]
  CS --> NOI[Net Operating Income Approach<br/>Durand]
  CS --> Tr[Traditional Approach]
  CS --> MM[Modigliani-Miller<br/>1958 / 1963]
  CS --> TO[Trade-Off Theory]
  CS --> PO[Pecking Order<br/>Myers, 1984]
  CS --> SG[Signaling Theory<br/>Ross, 1977]
  CS --> AG[Agency Cost Theory<br/>Jensen & Meckling, 1976]
  style CS fill:#E8F0FE,stroke:#1A73E8
  style MM fill:#E8F5E9,stroke:#2E7D32

29.3.1 Net Income (NI) Approach — Durand

David Durand’s Net Income approach (1952) assumes that $K_d$ and $K_e$ are independent of leverage. As a firm substitutes cheaper debt for costlier equity, WACC falls and firm value rises. The implication: an all-debt capital structure is theoretically optimal.

29.3.2 Net Operating Income (NOI) Approach — Durand

Durand’s NOI approach (1952) is the polar opposite. As leverage rises, $K_e$ rises exactly enough to offset the cheaper debt, leaving WACC constant and firm value invariant with respect to capital structure. In short, capital structure is irrelevant — there is no optimum.

29.3.3 Traditional Approach

The Traditional (or Intermediate) view sits between NI and NOI. It accepts a moderate amount of debt lowers WACC and raises firm value, but excessive debt raises $K_e$ disproportionately and ultimately raises WACC. The implication: there is an optimum capital structure where WACC is at its minimum — but it is reached through prudent leverage, not extreme.

The Three Pre-MM Approaches Compared

Approach	Behaviour of $K_e$	Behaviour of $K_d$	Behaviour of WACC	Optimum capital structure?
Net Income (NI)	Constant	Constant	Falls with leverage	All-debt
Net Operating Income (NOI)	Rises with leverage	Constant	Constant	Irrelevant
Traditional	Rises only after a point	Rises only at high leverage	U-shaped	Yes, at minimum WACC

29.3.4 Modigliani-Miller (MM) Approach

Franco Modigliani and Merton Miller’s 1958 paper revolutionised the field. It established two propositions in a frictionless world (no taxes, no bankruptcy cost, no agency cost, perfect information, perfect capital markets) (mm1958?):

MM Propositions — No-Tax World (1958)

Proposition	Statement
Proposition I	Firm value $V$ is independent of capital structure: $V_L = V_U$
Proposition II	Cost of equity rises with leverage: $K_e = K_o + (K_o - K_d) \cdot \frac{D}{E}$

The argument is arbitrage: if two firms with identical operating cash flows had different values purely because of leverage, investors could arbitrage the gap by home-made leverage (borrowing personally), restoring equality.

In their 1963 follow-up, MM relaxed the no-tax assumption. With corporate taxes and tax-deductibility of interest, the levered firm enjoys an interest tax shield, and:

\[ V_L = V_U + t \cdot D \]

— firm value rises linearly with leverage. The 1963 prescription is therefore all-debt, mirroring NI but for a different reason. Subsequent literature — including Miller’s 1977 paper on personal taxes — partially reverses this prescription.

29.3.5 Trade-Off Theory

The trade-off theory puts the brake on the MM-1963 prescription. As debt rises, the firm enjoys a tax shield but also incurs financial-distress costs — bankruptcy, agency costs of debt, lost flexibility. The optimum is where the marginal tax shield equals the marginal expected financial-distress cost:

\[ V_L = V_U + \text{PV of tax shield} - \text{PV of financial-distress costs} \]

The trade-off theory predicts a target capital structure that varies with industry and firm characteristics — high for stable, asset-heavy firms; low for volatile, intangible-asset firms.

29.3.6 Pecking Order Theory — Myers (1984)

Stewart Myers’s pecking order theory (1984) argues that information asymmetry between managers and investors drives a preferred order of financing (myers1984?):

Internal funds → Debt → Equity

Firms prefer retained earnings (no information cost), then debt (low information cost), and finally equity (highest information cost — issuing equity signals over-valuation, depressing the share price). The pecking-order theory explains why highly profitable firms (which can self-finance) often have low leverage — the opposite of what trade-off theory predicts.

29.3.7 Signaling Theory — Ross (1977)

Stephen Ross’s signaling theory (1977) treats capital-structure choice as a signal about quality. A good firm signals confidence by taking on more debt (a costly signal that bad firms cannot mimic without risking bankruptcy). Higher debt therefore signals higher quality — though the signal works only when bankruptcy is genuinely costly.

29.3.8 Agency Cost Theory — Jensen & Meckling (1976)

Michael Jensen and William Meckling’s agency-cost approach (1976) reframes capital structure as an outcome of conflicts between three groups: shareholders, managers and creditors (jensen1976?):

Two Agency Conflicts in Capital Structure

Conflict	Mechanism	Capital-structure response
Manager vs Shareholder	Managers may divert free cash flow to perquisites or empire-building	More debt commits free cash flow to interest payments — Jensen’s “free cash flow” hypothesis
Shareholder vs Creditor	Shareholders may shift risk on creditors via underinvestment, asset substitution	Less debt (or covenants, collateral) to limit risk-shifting

The optimum balances the two conflicts.

29.4 Leverage Analysis

Leverage is the use of fixed-cost obligations (operating fixed costs, financial fixed costs) to amplify returns. Three measures recur in the syllabus.

Three Measures of Leverage

Measure	Formula	What it measures
Operating Leverage (DOL)	$\dfrac{\% \Delta \text{EBIT}}{\% \Delta \text{Sales}} = \dfrac{\text{Contribution}}{\text{EBIT}}$	Sensitivity of EBIT to changes in sales — business risk
Financial Leverage (DFL)	$\dfrac{\% \Delta \text{EPS}}{\% \Delta \text{EBIT}} = \dfrac{\text{EBIT}}{\text{EBIT − Interest}}$	Sensitivity of EPS to changes in EBIT — financial risk
Combined Leverage (DCL)	$\text{DOL} \times \text{DFL} = \dfrac{\% \Delta \text{EPS}}{\% \Delta \text{Sales}} = \dfrac{\text{Contribution}}{\text{EBIT − Interest}}$	Total sensitivity of EPS to sales

A high DOL indicates that a small change in sales produces a large change in EBIT — typical of capital-intensive industries. A high DFL means a small change in EBIT produces a large change in EPS — typical of debt-heavy firms.

29.4.1 Worked example

Sales 1,00,000 units at ₹10 each; variable cost ₹6 per unit; fixed operating cost ₹2,00,000; interest ₹50,000.

Contribution = 1,00,000 × (10 − 6) = ₹4,00,000.
EBIT = 4,00,000 − 2,00,000 = ₹2,00,000.
EBT = 2,00,000 − 50,000 = ₹1,50,000.
DOL = 4,00,000 ÷ 2,00,000 = 2.
DFL = 2,00,000 ÷ 1,50,000 = 1.33.
DCL = 2 × 1.33 = 2.66.

A 10 per cent rise in sales would produce a 26.6 per cent rise in EPS.

29.5 EBIT-EPS Analysis and Indifference Point

The EBIT-EPS analysis compares alternative financing plans by tracking how EPS changes as EBIT changes. The indifference point (or break-even point in EBIT-EPS analysis) is the EBIT at which two financing plans yield the same EPS. It is computed by setting:

\[ \frac{(EBIT - I_1)(1 - t) - D_p}{N_1} = \frac{(EBIT - I_2)(1 - t) - D_p}{N_2} \]

and solving for EBIT, where $I$ is interest, $D_p$ is preference dividend, $N$ is the number of equity shares under each plan.

Below the indifference point, the less levered plan gives higher EPS; above it, the more levered plan gives higher EPS. The decision rule is to choose the more levered plan if expected EBIT is comfortably above the indifference point — but the risk must also be acceptable.

29.6 Business Risk vs Financial Risk

Business Risk vs Financial Risk

Dimension	Business Risk	Financial Risk
Source	Variability of operating earnings (EBIT)	Use of debt and other fixed-charge financing
Measured by	Operating Leverage (DOL)	Financial Leverage (DFL)
Drivers	Industry, demand volatility, operating leverage	Capital structure
Manageability	Hard to alter — structural	Alterable through capital-structure decision

29.7 Exam-Pattern MCQs

Q 01

Which of the following is not a determinant of capital structure?

ACost of capital
BStability of earnings
CRecipe of the company's lunch menu
DAsset structure

View solution

Correct Option: C

The lunch menu is irrelevant; the other three are textbook determinants.

Q 02

Match the capital-structure theory with its principal claim:

	Theory		Claim
(i)	Net Income approach	(a)	Capital structure is irrelevant — WACC and value invariant
(ii)	Net Operating Income approach	(b)	More debt always lowers WACC; all-debt is optimal
(iii)	Traditional approach	(c)	Information asymmetry: internal → debt → equity
(iv)	Pecking order (Myers, 1984)	(d)	An optimum exists where WACC is minimised; U-shaped WACC

A(i)-(b), (ii)-(a), (iii)-(d), (iv)-(c)
B(i)-(a), (ii)-(b), (iii)-(c), (iv)-(d)
C(i)-(c), (ii)-(d), (iii)-(b), (iv)-(a)
D(i)-(d), (ii)-(c), (iii)-(a), (iv)-(b)

View solution

Correct Option: A

Q 03

Modigliani and Miller's 1958 Proposition I states that, in a frictionless world:

AFirm value rises with leverage in proportion to the tax shield
BFirm value is independent of capital structure
CCost of equity falls with leverage
DCapital structure determines firm value uniquely

View solution

Correct Option: B

Proposition I — irrelevance of capital structure in a no-tax world.

Q 04

Match each capital-structure theorist with the year of the contribution:

	Theorist		Year
(i)	Modigliani and Miller (no tax)	(a)	1976
(ii)	Jensen and Meckling	(b)	1958
(iii)	Ross — signaling	(c)	1984
(iv)	Myers — pecking order	(d)	1977

A(i)-(b), (ii)-(a), (iii)-(d), (iv)-(c)
B(i)-(a), (ii)-(b), (iii)-(c), (iv)-(d)
C(i)-(c), (ii)-(d), (iii)-(b), (iv)-(a)
D(i)-(d), (ii)-(c), (iii)-(a), (iv)-(b)

View solution

Correct Option: A

Q 05

A firm's contribution is ₹6,00,000, EBIT ₹3,00,000, EBT ₹1,80,000. The Combined Leverage is:

A2.00
B2.33
C3.33
D3.50

View solution

Correct Option: C

DOL = 6,00,000/3,00,000 = 2; DFL = 3,00,000/1,80,000 ≈ 1.667; DCL = 2 × 1.667 = 3.33.

Q 06

Under the MM with-tax model (1963), firm value satisfies:

A$V_L = V_U$
B$V_L = V_U + t \cdot D$
C$V_L = V_U − t \cdot D$
D$V_L = V_U / (1 + t \cdot D)$

View solution

Correct Option: B

The interest tax shield gives $V_L = V_U + t \cdot D$.

Q 07

Arrange the following capital-structure theories in chronological order of their publication: (i) Pecking Order — Myers (ii) MM Proposition I (no tax) (iii) Agency Cost — Jensen & Meckling (iv) Signaling — Ross

A(ii), (iii), (iv), (i)
B(i), (ii), (iii), (iv)
C(iii), (ii), (i), (iv)
D(iv), (i), (iii), (ii)

View solution

Correct Option: A

MM (1958) → Jensen & Meckling (1976) → Ross (1977) → Myers (1984).

Q 08

Match each leverage with what it measures:

	Leverage		What it measures
(i)	Operating Leverage	(a)	Sensitivity of EPS to EBIT
(ii)	Financial Leverage	(b)	Sensitivity of EBIT to sales
(iii)	Combined Leverage	(c)	Total sensitivity of EPS to sales

A(i)-(b), (ii)-(a), (iii)-(c)
B(i)-(a), (ii)-(b), (iii)-(c)
C(i)-(c), (ii)-(a), (iii)-(b)
D(i)-(b), (ii)-(c), (iii)-(a)

View solution

Correct Option: A

Quick recall

Capital structure = mix of long-term sources. Financial structure = capital structure + current liabilities.
Optimum = mix that minimises WACC and maximises firm value.
Three pre-MM approaches: NI (debt good — all-debt optimal), NOI (debt irrelevant), Traditional (debt good up to a point — U-shaped WACC).
MM (1958): Proposition I — value invariant; Proposition II — $K_e = K_o + (K_o - K_d) D/E$; via arbitrage / home-made leverage.
MM (1963) with corporate tax: $V_L = V_U + tD$ — debt good for tax shield.
Trade-Off: $V_L = V_U + PV(\text{tax shield}) - PV(\text{distress cost})$.
Pecking Order (Myers 1984): internal → debt → equity (information asymmetry).
Signaling (Ross 1977): high debt = good-quality signal.
Agency (Jensen & Meckling 1976): debt curbs free-cash-flow misuse but raises shareholder-creditor conflict.
Three leverages: DOL = Contribution / EBIT; DFL = EBIT / (EBIT − Interest); DCL = DOL × DFL = Contribution / (EBIT − Interest).
Indifference point in EBIT-EPS analysis = EBIT at which two plans give the same EPS.
Business risk ↔︎ DOL; Financial risk ↔︎ DFL.