In 1992, Eugene Fama and Kenneth French published a paper that changed academic finance for good. They showed that the market alone could not explain stock returns. Two other measurable traits did a lot of the work: company size and the ratio of book value to market price. The CAPM model that had ruled for decades was incomplete.

That paper opened a 30 year research programme into what are now called factors: measurable stock characteristics that have predicted returns across markets, decades and countries. The important ones show up in Indian data too, and NSE now runs an index for almost every one of them.

A factor is a measurable characteristic of a stock that research has linked to returns above the market over long periods. Same signal, every stock, applied the same way for years. Not a tip. A rule.

5

classic factors: value, momentum, quality, low volatility, size

Academic literature since 1992

18.30%

Nifty200 Momentum 30 TRI, CAGR since April 2005

NSE Indices factsheet, 30 Sep 2026

13.46%

Nifty 200 TRI, CAGR since January 2004, the parent universe

NSE Indices factsheet, 30 Sep 2026

−0.47%

the same momentum index over the last 12 months

NSE Indices factsheet, 30 Sep 2026

Read those four numbers together and you have the whole story of factor investing. A long run premium that is real. And stretches, like the year to September 2026, when it simply does not show up. Part of the momentum index's long history is NSE's back calculation from before its launch in August 2020, so treat the early years as a model, not a track record.

The Fama-French foundation

Fama & French (1992), Three-Factor Model
Expected Return = Market Risk + Size Premium + Value Premium
The original paper showing small cap stocks and high book to market (cheap) stocks earned returns that market risk alone did not explain. The formal start of factor investing as an academic discipline.
Fama, E. & French, K. (1992). The Cross-Section of Expected Stock Returns. Journal of Finance.
Fama & French (2015), Five-Factor Model
Expected Return = Market + Size + Value + Profitability + Investment
Two decades later: profitability (companies that earn more consistently) and investment (companies that invest conservatively) were added as return predictors. Momentum, documented in 1993, sits alongside as the most studied factor outside the model.
Fama, E. & French, K. (2015). A Five-Factor Asset Pricing Model. Journal of Financial Economics.
Fama-French Data Library, Factor returns, methodology, data
  1. CAPM

    One factor: the market. Riskier stocks should earn more, nothing else matters.

  2. Three factor model

    Size and value added. Cheap and small stocks earned more than CAPM predicted.

  3. Momentum

    Jegadeesh and Titman: recent winners kept winning for months.

  4. Five factor model

    Profitability and investment join. Quality gets an academic home.

  5. Nifty200 Momentum 30 launches

    NSE factor indices make each premium something you can track, then own.

  6. Nifty200 Value 30 launches

    The value premium gets its own large and mid cap index in India.

The five major factors

Value
Cheap stocks outperform expensive ones over time
Signal: Low P/B · Low P/E · Low EV/EBITDA
Stocks trading at a low price relative to book value, earnings or cash flow have historically earned more than expensive glamour stocks. Markets overpay for excitement and underpay for boring, unloved businesses. Mean reversion does the rest, eventually.
In India: PSU banks, energy and commodity stocks often fill value screens. The Nifty200 Value 30 traded at 8.9 times earnings and 1.2 times book on 30 Sep 2026, against 19.4 and 2.8 for the Nifty 50. Its total return over the five years to that date: 22.9% a year, the best of the major factor indices.
Momentum
Recent winners keep winning over 3 to 12 months
Signal: trailing 6 and 12 month return, often skipping the latest month
Stocks that outperformed over the past 6 to 12 months tend to keep outperforming for a few more months. The classic academic signal is the 12 month return minus the latest month, which tends to reverse. NSE's momentum indices blend 6 and 12 month returns and divide by volatility. The usual explanation: markets underreact to good news and adjust slowly.
In India: one of the strongest long run factors in NSE data, and one of the most violent. The Nifty200 Momentum 30 earned 18.3% a year since April 2005 on total return, including NSE's back calculated years, and fell 30.7% from peak to trough in the two years to 9 Oct 2026. Several RupeeCase strategies, Allcap among them, rank stocks by momentum inside an NSE universe.
Quality
Profitable, low debt businesses outperform over cycles
Signal: High ROE · Low D/E · Stable earnings
Companies with high profitability, low leverage and steady earnings tend to compound more reliably than weak businesses. The market only partly prices in how long a durable advantage lasts. Linked to the Fama French profitability factor.
In India: NSE tracks it through the NIFTY100 Quality 30 and NIFTY200 Quality 30. Quality is powerful here because governance varies so widely across listed companies. It is also often expensive: the NIFTY200 Quality 30 traded at 7.9 times book on 30 Sep 2026, and its price fell 6.9% over the year to that date.
Low Volatility
Less volatile stocks deliver better risk adjusted returns
Signal: Low standard deviation of daily returns over a year
The low volatility anomaly is counterintuitive: theory says more risk should mean more return. In practice, calmer stocks have delivered similar or better returns with less risk. The usual explanation: investors overpay for lottery ticket stocks and underpay for stable, boring ones.
In India: FMCG, pharma and consumer staples often rank high. NSE tracks it through the Nifty100 Low Volatility 30 and Nifty Low Volatility 50. It does what it says on the box: over the two years to 9 Oct 2026 the Nifty100 Low Volatility 30 moved with 12.0% volatility against 13.2% for the Nifty 50. Combined with momentum, it softens the falls.
Size
Small caps earn higher returns than large caps over time
Signal: Low market capitalisation
Smaller companies have historically earned more than larger ones, the original Fama French finding. Small caps get less analyst coverage, trade less and are mispriced more often, and investors want paying for that risk. The size premium is real, lumpy, and can vanish for years.
In India: the premium has shown up in the Nifty Midcap 150 and Smallcap 250, with deeper falls. Liquidity is the catch: many small caps trade too little to take meaningful money without moving the price. Module 3.5 covers it in depth.
Five years to Sep 2026: value led, quality and momentum lagged the market

Total return CAGR, 5 years to 30 Sep 2026

  1. Nifty200 Value 3022.91%
  2. Midcap150 Momentum 5015.13%
  3. Nifty Alpha 5012.03%
  4. Nifty200 Momentum 309.28%
  5. Alpha Low Volatility 308.57%
  6. Nifty 200 (parent)8.30%
  7. NIFTY200 Quality 306.40%
  8. Nifty 506.38%

Source: NSE Indices factsheets, 30 Sep 2026, total return indices. Index history, not a promise of future returns.

Look at where quality sits. Over five years to September 2026, the factor with the best long run reputation in India barely beat the Nifty 50. Value, which had been written off for most of the 2010s, led by a wide margin. Nobody's model said that in 2021. That is the honest texture of factor investing: the premium is long run, and the run is longer than most people's patience.

Why factors persist

If factors earn excess returns, why doesn't everyone exploit them until they disappear? Three answers, and they work together:

1
Risk based explanations
Some factors may be pay for real economic risk. Value stocks are often companies under stress, cheap because they are risky. You earn more because you carry a real chance of permanent loss.
2
Behavioural explanations
Some factors persist because of human bias. Momentum exists partly because investors underreact to news, so prices adjust slowly. Low volatility persists because investors overpay for exciting stocks and underpay for boring ones. As long as the biases exist, the premia should too.
3
Structural and institutional explanations
Fund managers are judged against benchmarks every quarter. Few can hold a value tilt that lags for two or three years, even when the thesis is right. Those limits leave mispricing on the table for anyone who can sit through the wait.

The honest caveat: factor premia are real but not smooth. Value lagged for most of the 2010s before its run from 2021. Momentum can fall 30% or more in sharp reversals: the Nifty200 Momentum 30 did exactly that between October 2024 and October 2026. Size premia disappear in large cap bull markets. Factors need patience measured in years, which is why combining them smooths the ride. Module 3.6 shows how.

NSE Indices, Factor & Strategy Indices (Momentum, Quality, Value, Low Vol)

A worked example: reading a momentum score

The classic academic momentum signal is the return over the last 12 months, skipping the most recent month. Say a stock is up 40% over 12 months, and 8% of that came in the latest month. The 12 minus 1 momentum is (1.40 ÷ 1.08) minus 1, about 29.6%. Rank every stock in the universe on that number, take the top slice, and you have a momentum portfolio.

12 minus 1 momentum, from two returns

Momentum score 29.6%

Formula: (1 + 12 month return) ÷ (1 + 1 month return) minus 1. NSE's own momentum indices use a volatility adjusted blend of 6 and 12 month returns.

Why skip the last month? Because very short term winners tend to give a little back the next month, a reversal effect, and skipping it keeps that noise out of the score. NSE's Nifty200 Momentum 30 goes a step further: it averages 6 and 12 month returns, each divided by the stock's volatility, so a steady climber outranks a stock that got there in one wild week.

What each factor actually owns

Index, 30 Sep 2026P/EP/BDividend yieldBeta to Nifty 50 (5Y)
Nifty 5019.362.781.22%1.00
Nifty200 Value 308.861.212.22%1.12
NIFTY200 Quality 3025.667.931.86%0.82
Nifty200 Momentum 3023.214.290.86%1.18

Source: NSE Indices factsheets, 30 Sep 2026.

The fingerprints are clear. Value buys cheap and gets paid a dividend for waiting. Quality pays up for great balance sheets and moves less than the market. Momentum owns whatever has been going up, which is why its beta is the highest and its falls the hardest.

MythOnce a factor is published, the edge is arbitraged away.

FactPremia shrink after publication but have not vanished, because they rest on behaviour and career risk. Momentum was published in 1993; NSE's momentum index still earned 18.3% a year from 2005 to 2026, back calculated years included.

Common mistakes with factors

Buying last year's best factor. That is momentum applied to factors, and it often lands you at the top of a cycle. Value looked dead in 2020. Quality looked unbeatable in 2021.

Reading a back calculated history as a track record. Most NSE factor indices launched between 2017 and 2024. Their earlier years are a model.

Quitting in year two. Every factor has multi year droughts. If you cannot hold through one, a single factor is the wrong tool for you.

Mistaking a label for a factor. A fund called "value" that holds expensive stocks is not a value strategy. Check the P/B and P/E of what it owns.

How this shows up in RupeeCase

Each RupeeCase strategy is a factor rule you can read. Most of the current lineup ranks stocks by momentum inside an NSE universe and rotates on a fixed cadence; the Allcap Multi Asset strategy adds a 10% debt and 10% gold sleeve to soften the momentum ride. The strategy pages show each rule, its universe and its model, back tested history, so you can see the factor and its bad years side by side before investing.

Which factor is best for India?

None wins every period. Over the long run momentum and value have both earned premiums in NSE data, quality has been steady, and low volatility has cut risk. The order changes every few years, which is why most systematic investors hold more than one.

Are factor index returns before launch real?

No. NSE computes them by applying today's rules to past data, which is a back test. They are useful for understanding the rule, not as proof of what an investor actually earned.

Is a smart beta fund the same as a factor strategy?

Usually yes: smart beta is the industry name for an index fund that tracks a factor index instead of a market cap index. Check which index it follows, how often it rebalances and what it costs.