Warren Buffett’s Style Drift

Your source for free real-time insider trading data, Insider Monkey, used Carhart’s (1997) four-factor model to estimate Warren Buffett’s alpha and investment style between 1997 and 2009. The four factors used in the regression can be downloaded at Ken French’s website. They are market factor, size, book-to-market, and momentum. We used Berkshire Hathaway’s (BRK) monthly returns to proxy Warren Buffett‘s performance. Here are the regression results for each decade ending in 1989, 1999, and 2009:

hedge funds vs. mutual funds

Regression 10 Years Ending December 1989

During the 10 years ending in December 1989, Warren Buffett’s alpha was 1.1% per month. His beta was 1, benefitting 100% from increases in the general market. He also invested in small cap stocks, distressed stocks, and stocks with high momentum. All of these coefficients are significant at the 10% level.

Regression 10 Years Ending December 1999

During the 10 years ending in December 1999, Warren Buffett’s alpha was 0.63% per month. His beta was 1.1, benefitting 110% from increases in the general market. He also invested in large cap stocks, distressed stocks, and stocks with no momentum. All of these coefficients (except his alpha) are significant at the 10% level.

Regression 10 Years Ending December 2009

During the 10 years ending in December 2009, Warren Buffett’s alpha was 0.06% per month, which is technically zero. His beta was 0.35, reflecting all the cash he had been hoarding in his portfolio. He had also been investing in distressed stocks (stocks with high book-to-market ratios), a practice he continues.

It’s really interesting to see that Warren Buffett’s alpha disappeared over the 10 years ending December 2009.

blog comments powered by Disqus
Insider Monkey Headlines
Insider Monkey Small Cap Strategy
Insider Monkey Small Cap Strategy

Insider Monkey beat the market by 52 percentage points in 24 months. Our beta is only 1.2 (don't click this link if beating the market isn't important to you).

Lists

On the Move: The 10 Fastest Growing Businesses in 2015

Fast Money: The 10 Highest Paying Fast Food Restaurants

Mixing It Up: The 14 Best Music Mashups of 2014

Rito Pls Buff: The 10 Least Played Champions in LoL Season 4

10 Covers of Popular Songs that are Better than the Originals

Must See TV: The 9 Most Anticipated Shows of 2015

The 15 Biggest Box Office Bombs of All Time

10 Things The World Can’t Stand About Americans

Picture Perfect: The 6 Smartphones with the Best Cameras

The 10 Best Countries To Work In the World

A Profitable Day At The Track: 5 Tips For Betting On Horses

Tearing You Apart: 6 Bad Habits That Ruin Relationships

Learning on the Job: The 6 Biggest Mistakes Parents Make

Shopaholics Rejoice: The 12 Biggest Malls in the World

Fright Night: 10 Horror Movies Based on True Stories

Mach Mania: The 10 Fastest Jets in the World

Military Heavyweights: The 10 Countries with the Most Tanks

All In: The 7 Richest Poker Players in the World

Abracadabra: The 10 Best Magicians in the World

The 10 Richest Asian Countries in the World in 2014

Eyes in the Sky: 10 Things You Need to Know About Drones

Rising Stars: The 6 Best Silicon Valley Startups

Military Muscle: The 5 Most Advanced Armies in South America

All that Glitters: The 7 Most Luxurious Jewelry Brands in the World

5 Things You Didn’t Know About ISIS but Should

Empowering Your Money: The 5 Best Energy Stocks to Invest In

The 11 Best Android Apps You Can’t Get on iOS

The 10 Most Important International Conflicts in 2014

Mood Enhancers: The 20 Most Uplifting Songs of all Time

Lover Beware: The 8 Countries that Cheat the Most

Breath of Fresh Air: The 25 Countries with the Best Air Quality on the Planet

Singles Beware: The 8 Worst Mistakes Made on First Dates

Healthy and Happy: The 10 Countries with Lowest Healthcare Costs

The 6 Best Company Team Building Activities to Build Workplace Camaraderie

Ships Ahoy: The 10 Busiest Shipping Ports in the World

10 Productivity Tips to Save You Time and Help You Do More With Less

Grab a Bite: The Most Popular Fast Food Restaurants in America

Friday Night Thirst: The 10 Most Popular Cocktails in the World

The 6 Greatest Unsolved Mysteries We May Never Figure Out

7 Useless Products You Never Should’ve Bought

The 5 Reasons Why You’re Single and Miserable

The 7 Most Addictive Foods in the World We Can’t Stop Eating (Even Though We Should)

5 Amazing Places You Can Swim with Dolphins

The Top 7 Most Livable Countries In The World

The 10 Most Expensive Baseball Cards Ever Pulled From A Pack

The 5 Easiest Second Languages to Learn for English Speakers

Silver Spoon: The 6 Richest Families in the World

The 20 Countries with the Largest Prison Populations in the World

The Top 10 Richest Actors in the World

The 10 Best Airline Stocks to Invest In Before They Fly Too High

Subscribe

Enter your email:

Delivered by FeedBurner

X

Thanks! An email with instructions is sent to !

Your email already exists in our database. Click here to go to your subscriptions

Insider Monkey returned 47.6% in its first year! Wondering How?

Download a complete edition of our newsletter for free!