Learn index vs stock futures

5.1.10 · Stock-Market › Futures

Overview

Index futures aur stock futures dono derivative contracts hain jo buyer ko obligate karte hain ki wo ek underlying asset ko ek predetermined future date aur price par purchase kare (ya seller ko sell karne ke liye). Critical difference yeh hai ki kya track karte hain: index futures ek basket of stocks (ek index) track karte hain, jabki stock futures individual company shares track karte hain.

Core Concepts

[!definition] Stock Futures

Ek stock future ek standardized contract hai jo ek single company ke specific quantity of shares ko ek predetermined price par ek future date mein buy ya sell karne ke liye hota hai. India mein, ek stock futures contract typically 1 lot represent karta hai (lot size stock ke hisaab se vary karti hai, jaise kuch ke liye 250 shares, kuch ke liye 500).

Key characteristics:

• Underlying: Single stock (e.g., Reliance, TCS, HDFC Bank)
• Exposure: Company-specific risk
• Volatility: Higher (company news, earnings, management changes se affected)
• Trading: NSE/BSE market hours ke dauran
• Settlement: Cash-settled ya physical delivery (India mein, mostly cash)

[!definition] Index Futures

Ek index future ek contract hai jo stock market index par based hai - jo multiple stocks ka weighted average hota hai. Index khud physically deliver nahi kiya ja sakta; ye hamesha cash-settled hote hain.

Key characteristics:

• Underlying: Market index (e.g., Nifty 50, Bank Nifty, Sensex)
• Exposure: Diversified market risk
• Volatility: Lower (bahut saare stocks mein smoothed)
• Lot size: Varies karta hai (Nifty 50 = 50 units, Bank Nifty = 25 units)
• Settlement: Hamesha cash-settled

[!intuition] Do Types Kyun Exist Karte Hain

Aise socho: stock futures tumhe bet karne dete hain ki Apple market ko outperform karega ya nahi, jabki index futures tumhe bet karne dete hain ki poora tech sector (ya poora market) rise karega ya fall karega.

Ek ko doosre ke upar kyun choose karoge?

1. Diversification needs: Index futures instant diversification dete hain. Agar tumhe lagta hai "market rally karegi" lekin nahi pata kaunse specific stocks, toh Nifty futures kharido. Agar tumhara belief hai "Reliance market ko beat karega", toh Reliance futures kharido.

2. Risk appetite: Stock futures mein idiosyncratic risk hoti hai (company-specific events jaise CEO ka resign karna, earnings miss). Index futures mein sirf systematic risk hoti hai (overall market movements).

3. Capital efficiency: Index futures often lower margins require karte hain relative to jo exposure provide karte hain, kyunki index ki volatility individual stocks se lower hoti hai.

4. Hedging strategy:

   • Portfolio manager jo 30 stocks hold kar raha hai → index futures se hedge karo (30 individual hedges se simpler)
   • Investor jo sirf Infosys hold kar raha hai → Infosys stock futures se hedge karo (precise hedge)

Detailed Comparison

[!formula] Contract Value Calculation

Stock Futures ke liye: $\text{Contract Value}=\text{Lot Size}\times \text{Futures Price}$

Yeh formula kyun? Lot size exchange dwara fix hoti hai (standardization requirement). Futures price no-arbitrage condition (cost-of-carry model) dwara determine hoti hai. Multiply karne par total notional exposure milta hai.

Example: Reliance futures with lot size 250, trading at ₹2,500 $\text{Contract Value}=250\times 2500=₹6,25,000$

Index Futures ke liye: $\text{Contract Value}=\text{Lot Size}\times \text{Index Level}$

Yeh kaise kaam karta hai? Index level (e.g., Nifty at 18,500) ek "price" nahi balki ek weighted average hai. Exchange ek lot size assign karta hai (Nifty ke liye, yeh 50 hai) taaki is dimensionless number ko ek tradeable contract mein convert kiya ja sake.

Example: Nifty 50 at 18,500 with lot size 50 $\text{Contract Value}=50\times 18500=₹9,25,000$

[!formula] Margin Requirements

Exchange margins calculate karne ke liye SPAN (Standard Portfolio Analysis of Risk) margins use karta hai. Formula complex hai, lekin principle yeh hai:

$\text{Margin}=\text{VaR}(\text{portfolio},99\%,1\text{-day})+\text{ELM}$

Jahan:

• VaR = Value at Risk (1 din mein 99% confidence ke saath worst expected loss)
• ELM = Extreme Loss Margin (tail risk buffer)

Index margin lower kyun hoti hai? Diversification! Index ki daily volatility lower hoti hai kyunki individual stock movements partially cancel out ho jaate hain.

Typical margins (rule of thumb):

• Nifty futures: Contract value ka 10-12%
• Stock futures: 15-40% (volatile stocks ke liye higher)

[!example] Worked Example 1: Index Futures se Hedging

Scenario: Aap ek ₹50 lakh portfolio manage karte ho jo Nifty 50 ko closely track karta hai. Tumhe agle mahine market correction ka dar hai lekin apni holdings sell nahi karna chahte (tax implications, transaction costs).

Step 1: Hedge ratio calculate karo $\text{Number of contracts}=\frac{\text{Portfolio Value}}{\text{Contract Value}}=\frac{50,00,000}{50\times 18,500}=\frac{50,00,000}{9,25,000}\approx 5.4$

Yeh step kyun? Tumhe itne futures contracts chahiye ki agar index 1% gire, tumhara futures gain tumhare portfolio ke 1% loss ko offset kare.

Step 2: Round karo aur execute karo 5 Nifty futures contracts short karo (conservative hedge ke liye round down).

Step 3: Outcome analysis

• Agar Nifty 5% girkar 17,575 ho jaye:
  • Portfolio loss: ₹50L × 5% = ₹2,50,000
  • Futures gain: 5 contracts × 50 × (18,500 - 17,575) = 5 × 50 × 925 = ₹2,31,250
  • Net loss: ₹18,750 (rounding aur tracking error ki wajah se imperfect hedge)

Yeh kaam kyun karta hai? Index futures tumhare portfolio ke saath nearly 1:1 move karte hain (assuming high correlation), isliye inhe short karna ek offsetting position create karta hai.

[!example] Worked Example 2: Stock Futures se Speculation

Scenario: Tumhara maanna hai ki Tata Motors agले hafte strong EV sales announce karega. Current price ₹650, futures ₹655 (lot size 1,500).

Step 1: Investment calculate karo Margin required (assume 20%): ₹655 × 1,500 × 0.20 = ₹1,96,500

Yeh step kyun? Tum full contract value (₹9,82,500) nahi pay karte, sirf margin. Yahi leverage hai.

Step 2: 1 lot kharido Tum 1 Tata Motors futures contract ₹655 par kharido.

Step 3: Outcome (price ₹700 tak rise karta hai)

• Profit: (₹700 - ₹655) × 1,500 = ₹67,500
• Return on margin: ₹67,500 / ₹1,96,500 = 34.35%
• Actual stock movement: (₹700 - ₹650) / ₹650 = 7.69%

Difference kyun? Leverage! Tumne ₹9.8L worth of stock control kiya sirf ₹1.96L se.

Step 4: Outcome (price ₹630 tak girti hai)

• Loss: (₹630 - ₹655) × 1,500 = -₹37,500
• Return on margin: -19.1%

Risk: Agar losses tumhara margin exceed kar dein, tumhe ek margin call aayega - tumhe funds add karne honge ya position liquidate ho jayegi.

[!example] Worked Example 3: Arbitrage Opportunity

Scenario: Nifty spot 18,500 par, Nifty futures (1-month) 18,650 par. Risk-free rate 6% p.a., koi dividends expected nahi.

Step 1: Fair value calculate karo Cost-of-carry use karke: $F=S\times e^{r\times t}=18,500\times e^{0.06\times \frac{1}{12}}=18,500\times e^{0.005}=18,500\times 1.00501=18,592.69$

Yeh step kyun? No-arbitrage market mein, futures ko spot price plus position carry karne ki cost (interest cost) par trade karna chahiye.

Step 2: Mispricing identify karo Futures 18,650 par > Fair value 18,592.69 → Futures ₹57.31 overpriced hain

Step 3: Arbitrage execute karo (Cash-and-Carry)

• ₹9,25,000 1 mahine ke liye 6% par borrow karo
• Nifty portfolio (index replicate karo) 18,500 par kharido
• Nifty futures 18,650 par becho
• Expiry tak hold karo

Yeh kaam kyun karta hai? Expiry par, futures spot se converge ho jaate hain. Tum:

1. Loan + interest repay karo: ₹9,25,000 × (1 + 0.06/12) = ₹9,29,625
2. Portfolio ko spot par becho (= futures settlement): 18,650 × 50 = ₹9,32,500
3. Profit: ₹9,32,500 - ₹9,29,625 = ₹2,875 risk-free

Real-world note: Transaction costs aur tracking error aisi mispricings ko jaldi eliminate kar dete hain.

Common Mistakes

[!mistake] Mistake 1: Individual Stocks Hedge Karne ke Liye Index Futures Use Karna

Wrong approach: Sirf Infosys hold karo, Nifty futures short karke hedge karo.

Kyun sahi lagta hai: "Infosys Nifty mein hai, toh agar Nifty gire, Infosys bhi girega."

Steel-man argument: Yeh completely galat nahi hai - Infosys ka Nifty ke saath beta hota hai (systematic risk component). Agar poora market crash kare, Infosys bhi likely girta hai.

Phir bhi galat kyun hai: Infosys ka Nifty weight sirf ~3-4% hai. Uske movements company-specific factors (earnings, attrition, deal wins) se dominate hote hain. Hedge ratio yeh hogi:

$\text{Hedge contracts}=\frac{\text{Infosys Value}}{\text{Nifty Contract}}\times {\beta }_{\text{Infosys}}$

Perfect beta estimation ke baad bhi, tum sirf systematic risk hedge kar rahe ho. Agar Infosys-specific bad news aaye (CEO resign kare, contract loss), tum stock par toh lose karte hi ho, aur agar market rally kare toh short futures position par bhi lose karte ho.

Fix: Precise hedging ke liye Infosys stock futures use karo. Index futures sirf portfolio-level systematic risk ke liye use karo.

[!mistake] Mistake 2: Index Futures mein Basis Risk ko Ignore Karna

Wrong assumption: "Mera portfolio Nifty track karta hai, toh Nifty futures short karna perfect hedge hai."

Kyun sahi lagta hai: Math (hedge ratio calculation) bilkul tight lagti hai.

Steel-man: Agar tumhara portfolio IS the Nifty hai (same weights, same stocks), yeh perfectly kaam karta hai.

Kyun fail hota hai: Zyaadatar portfolios index se deviate karte hain:

• Different weights (kuch sectors mein overweight)
• Missing stocks (50 ki jagah 30 stocks hold karna)
• Tracking error time ke saath accumulate hoti hai

Example: Tumhare portfolio mein 30% IT stocks hain vs. Nifty ke 15%. Agar IT rally kare lekin broader market gire, tumhara portfolio rise kar sakta hai jabki Nifty gire. Tumhare short Nifty futures paise lose karte hain jabki tumhara portfolio expected se kam gain karta hai - double whammy.

Fix: Regression se apne portfolio ka beta to the Nifty calculate karo: $R_{\text{portfolio}}=\alpha +\beta \times R_{\text{Nifty}}+ϵ$

Beta se hedge ratio adjust karo: $\text{Contracts}=\frac{\text{Portfolio Value}}{\text{Contract Value}}\times \beta$

[!mistake] Mistake 3: Lot Size ko Share Quantity se Confuse Karna

Wrong calculation: "Nifty 18,500 par hai, mujhe ₹10L exposure chahiye, toh mujhe ₹10L / ₹18,500 = 54 contracts chahiye."

Kyun sahi lagta hai: Tum paise ko price se divide kar rahe ho, jaise stocks khareedna.

Kyun galat hai: Lot size bhool gaye! Har Nifty contract = 50 units.

Correct calculation: $\text{Contract Value}=50\times 18,500=₹9,25,000$ $\text{Contracts needed}=\frac{10,000}{9,25,000}=1.08\approx 1$

Fix: Hamesha calculate karo: Number of Contracts = Desired Exposure / (Lot Size × Futures Price)

Strategic Use Cases

Stock Futures Kab Use Karein:

1. Concentrated bet: Kisi specific company ki earnings, product launch, merger par high conviction
2. Event-driven trading: FDA approval, kisi specific sector stock par election impact
3. Pair trading: Stock A futures long, Stock B futures short (dono same sector mein, different fundamentals)
4. Covered calls on steroids: Leverage ke liye futures use karo jabki dusre opportunities ke liye cash rakho

Index Futures Kab Use Karein:

1. Market timing: Overall economy, interest rates, GDP growth par bullish/bearish
2. Portfolio hedging: Diversified holdings ko market crashes se bachao
3. Asset allocation shifts: Stock transactions ke bina quickly equity exposure gain/reduce karo
4. Arbitrage: Spot index aur futures ke beech mispricing exploit karo
5. Overnight exposure: Jab equity markets band hon tab market exposure lene ke liye futures use karo (futures ke liye limited hours)

Key Relationships

[!formula] Beta Relationship (Stock to Index)

${\beta }_{\text{stock}}=\frac{\text{Cov}({\text{R}}_{\text{stock}},{\text{R}}_{\text{index}})}{\text{Var}({\text{R}}_{\text{index}})}$

Yeh kyun important hai: Beta tumhe batata hai ki ek stock futures contract hedge karne ke liye kitne index futures contracts chahiye.

First principles se derivation:

Stock return decomposition se shuru karo: $R_{\text{stock}}=\alpha +\beta R_{\text{index}}+ϵ$

jahan $ϵ$ idiosyncratic risk hai (mean zero, index se uncorrelated).

$\beta$ find karne ke liye, dono sides ka $R_{\text{index}}$ ke saath covariance lo: $\text{Cov}(R_{\text{stock}},R_{\text{index}})=\beta \cdot \text{Cov}(R_{\text{index}},R_{\text{index}})+\text{Cov}(ϵ,R_{\text{index}})$

Kyunki $ϵ$ index se uncorrelated hai: $\text{Cov}(ϵ,R_{\text{index}})=0$

Aur $\text{Cov}(R_{\text{index}},R_{\text{index}})=\text{Var}(R_{\text{index}})$

Isliye: $\beta =\frac{\text{Cov}(R_{\text{stock}},R_{\text{index}})}{\text{Var}(R_{\text{index}})}$

Example: Agar Reliance ka $\beta =1.2$ Nifty ke saath hai:

• Nifty 1% upar → Reliance ke 1.2% rise hone ki expectation
• 1 lot Reliance futures hedge karne ke liye, $1.2\times \frac{\text{Reliance contract value}}{\text{Nifty contract value}}$ Nifty futures short karo

[!formula] Index as Weighted Average

$n$ stocks wale index ke liye: $I_t=\frac{{\sum }_{i=1}^n{w}_i\cdot P_{i,t}}{\text{Divisor}}$

Divisor kyun? Historical reasons - jab koi stock split ho ya replace ho, divisor adjust hota hai taaki index artificially jump na kare.

Weights kya hote hain?

• Free-float market cap weighted (Nifty, Sensex): $w_i=\frac{{\text{Market Cap}}_i}{\sum {\text{Market Cap}}_j}$
• Price-weighted (Dow Jones): Har stock ki price per share equally contribute karti hai

Yeh futures ko kaise affect karta hai? Ek large-cap stock (high weight) ka 1% movement index futures par zyada impact dalta hai bataniksi small-cap ke 5% movement se.

Connections

• Cost-of-Carry Model - Spot aur futures ke beech pricing relationship
• Margin Requirements SPAN - Risk-based margining system
• Beta and Systematic Risk - Stocks market indices ke saath kaise correlate karte hain
• Calendar Spreads - Near vs. far month futures trading
• Arbitrage Strategies - Index vs. stock mispricing exploit karna
• Portfolio Hedging Techniques - Risk management ke liye derivatives use karna
• Liquidity and Impact Cost - Index futures zyada volume kyun trade karte hain
• Options vs Futures - Alternative derivative instruments

[!mnemonic] Key Difference Yaad Rakho

"S.I.D - E.V.E."

• Stock futures: Single company

• Index futures: Index basket

• Diversification: Different risk profiles

• Exposure: Equity market (index) vs. entity-specific (stock)

• Volatility: Varied (stock > index)

• Efficiency: Portfolios ke liye index se Easier hedging

[!recall]- Ek 12-Saal ke Bachche ko Samjhao

Imagine karo tum aur tumhare dost trading cards collect karte ho.

Stock futures aise hain jaise apne dost se deal karna: "Ek mahine mein, main tumhari rare Pokémon card $50meinkhareedunga,chahetabuskipricekuchbhiho."Tumbetkarrahehokiwohekspecificcardtab$50 se zyada ki hogi. Agar us card ki price gir jaye kyunki player injured ho jaye ya card reprint ho jaye, phir bhi $50 pay karne padenge - ouch!

Index futures aise hain jaise ek poore starter deck (30 cards) ke liye deal karna. Tum bet kar rahe ho ki un saari cards ki average value badhegi. Shayad ek card crash kare, lekin agar zyaadatar cards achha karein, tum safe ho. Yeh aise hai jaise sirf ek student par bet karne ki jagah poori class ke test mein achha karne par bet karna.

Ek ko doosre ke upar kyun choose karoge?

• Agar tumhe sachchi lagta hai ki ek specific Pokémon (jaise Charizard) ek nayi movie ki wajah se super popular ho jayega, toh uss ek card par bet karo (stock futures).
• Agar tumhe bas lagta hai "trading cards generally popular ho rahi hain" lekin nahi pata kaunsi specific, toh poore deck par bet karo (index futures).

Cool part? Ab $50paykarnekizarooratnahi-basek"safetydeposit"(margin)rakhoshayad$10 ka. Agar tum sahi ho aur card/deck $60hojaye,$10 sirf $10depositparprofitbanateho-tumneapnapaisadoublekarliya!Lekinagargalathoauryeh$40 tak gire, woh $10 deposit lose ho jaata hai aur shayad aur bhi owe karna pad sakta hai.

Practice Questions

#flashcards/stock-market

Stock futures aur index futures ke beech key difference kya hai? :: Stock futures ek single company ke shares track karte hain, jabki index futures ek basket of stocks (market index) track karte hain. Stock futures mein higher volatility aur company-specific risk hoti hai; index futures mein lower volatility aur diversified market risk hoti hai.

Concept Map