Enter Values

%
Actual portfolio return (annualized)
%
Treasury or T-Bill rate (annualized)
%
Portfolio standard deviation (annualized)
%
Benchmark market return (annualized)
%
Market standard deviation (annualized, S&P 500 ~15%)
Ryan O'Connell, CFA
Calculator by Ryan O'Connell, CFA

Quick Reference

  • Positive M² = Outperformed market (risk-adjusted)
  • Negative M² = Underperformed market (risk-adjusted)
  • Expresses Sharpe ratio in percentage terms
  • All inputs must be annualized

M² Ratio Result

M² (Modigliani-Modigliani) +0.75% At Market
-3% 0% +5%
Portfolio Sharpe 0.417
Market Sharpe 0.367

Formula Breakdown

M² = (Sharpe_p − Sharpe_m) × σm
Step 1: Portfolio Sharpe = (12.00%4.50%) / 18.00% = 0.417
Step 2: Market Sharpe = (10.00%4.50%) / 15.00% = 0.367
Step 3: M² = (0.4170.367) × 15.00% = +0.75%

Interpretation

Your portfolio's M² of +0.75% means it outperformed the market by 0.75 percentage points on a risk-adjusted basis. If your portfolio's risk were adjusted to match the market, it would have returned 0.75% more than the market.

Rating Guide

M² represents percentage points of outperformance vs market. These are general guidelines for context.

< -2% Poor Significant underperformance
-2% to < 0% Below Market Underperforming risk-adjusted
0% to < 1% At Market In line with market
1% to < 2% Above Market Moderate outperformance
2% to < 4% Good Strong outperformance
≥ 4% Exceptional Verify data accuracy

Understanding the M² Ratio

What is the M² Ratio?

The M² (Modigliani-Modigliani) ratio, also known as M-squared or the Modigliani Risk-Adjusted Performance measure, expresses risk-adjusted portfolio performance in percentage terms rather than as a ratio. Named after Nobel laureate Franco Modigliani and his granddaughter Leah Modigliani, it was introduced in 1997.

M² answers the question: "If we adjusted this portfolio's risk to match the market, how much better or worse would it have performed?"

Key Insight: While the Sharpe ratio gives a number like "0.75" that requires context to interpret, M² gives a directly meaningful percentage like "+2%" that clearly shows you outperformed the market by 2 percentage points on a risk-adjusted basis.

Understanding the Formula

M² can be expressed in multiple equivalent ways:

  • Primary formula: M² = (Rp − Rf) × (σm / σp) − (Rm − Rf)
  • Using Sharpe ratios: M² = (Sharpe_portfolio − Sharpe_market) × σm
  • Intuitive form: M² = Sharpe_portfolio × σm − Market Risk Premium

The calculation involves three steps:

  1. Calculate Portfolio Sharpe: (Rp − Rf) / σp
  2. Calculate Market Sharpe: (Rm − Rf) / σm
  3. Calculate M²: (Sharpe difference) × market volatility

M² vs Sharpe Ratio

Both M² and Sharpe ratio use the same underlying information, but express results differently:

Aspect Sharpe Ratio M² Ratio
Output Ratio (e.g., 0.75) Percentage (e.g., +2%)
Interpretation Requires benchmark comparison Directly shows over/under performance
Best for Academic analysis, comparing portfolios Client communication, intuitive reporting

Interpreting Results

  • M² > 0: Portfolio outperformed the market on a risk-adjusted basis
  • M² = 0: Portfolio performed exactly in line with the market (same Sharpe ratio)
  • M² < 0: Portfolio underperformed the market on a risk-adjusted basis
Important: M² tells you risk-adjusted performance difference, not absolute return difference. A portfolio with M² = 2% might have higher or lower absolute returns than the market depending on its risk level.

Practical Applications

  • Manager evaluation: Compare fund managers on a risk-adjusted basis
  • Portfolio optimization: Identify if added risk is being compensated
  • Client reporting: Explain performance in intuitive percentage terms
  • Strategy comparison: Compare strategies with different risk profiles

Limitations

  • Backward-looking: Based on historical data, not predictive
  • Time period sensitive: Results vary significantly with measurement period
  • Assumes normal distribution: May not capture tail risks
  • Benchmark dependent: Results depend on market benchmark chosen

Consider using M² alongside Sharpe ratio, Jensen's alpha, and Treynor ratio for a complete picture of portfolio performance.

Frequently Asked Questions

The M² (Modigliani-Modigliani) ratio, also called M-squared, expresses risk-adjusted portfolio performance in percentage terms rather than as a ratio. Named after Franco and Leah Modigliani, it answers: "If we adjusted this portfolio's risk to match the market, what would be the excess return?" Unlike the Sharpe ratio which produces a ratio, M² produces a directly comparable percentage.

M² is calculated as: M² = (Rp − Rf) × (σm / σp) − (Rm − Rf), or equivalently: M² = (Sharpe_portfolio − Sharpe_market) × σm. For example, if portfolio return is 12%, risk-free rate is 4.5%, portfolio std dev is 18%, market return is 10%, and market std dev is 15%, then M² = (12% − 4.5%) × (15%/18%) − (10% − 4.5%) = 6.25% − 5.5% = 0.75%.

A positive M² indicates outperformance versus the market on a risk-adjusted basis. Generally, M² above 1% suggests moderate outperformance, while above 2% indicates strong performance. M² of zero means performance equivalent to the market after risk adjustment. Negative M² indicates underperformance versus the market benchmark.

Both M² and Sharpe ratio measure risk-adjusted returns, but they express results differently. Sharpe ratio produces a ratio (e.g., 0.75) that requires context to interpret. M² produces a percentage (e.g., 0.75%) that directly shows how much you outperformed or underperformed the market. M² = Sharpe × market volatility − market risk premium, making it easier to communicate performance.

M² is easier to interpret because it expresses performance in percentage points. When you say "M² = 2%", it clearly means outperforming the market by 2 percentage points on a risk-adjusted basis. Sharpe ratios require comparison to other Sharpe ratios to be meaningful. M² is particularly useful when communicating with clients or comparing portfolios with different risk levels.

Yes, M² can be negative. Negative M² indicates the portfolio underperformed the market on a risk-adjusted basis. For example, M² = −1.5% means the portfolio returned 1.5 percentage points less than the market would have returned at the same risk level. This could indicate poor security selection, bad timing, or high fees eroding returns.
Disclaimer

This calculator is for educational and informational purposes only. M² is a historical measure based on past data and may not predict future performance. The rating thresholds are general guidelines, not fixed industry standards. Results depend heavily on the time period selected and benchmark chosen. Investment decisions should consider multiple factors beyond risk-adjusted returns. Always consult with a qualified financial advisor before making investment decisions.