What Buffett’s 1981 Shareholder Letter Teaches Us About Moats, Inflation, and Smart Investing By Moat in You Warren Buffett’s 1981 letter to Berkshire Hathaway shareholders offers more than just a financial update. It’s filled with timeless lessons on investing discipline, the impact of inflation, and the value of owning businesses with enduring competitive advantages—or economic moats. Here’s a breakdown of the key takeaways in simple, conversational language. 1981 Performance Overview Berkshire earned $39.7 million in operating income in 1981, giving shareholders a 15.2% return on their beginning equity. That’s a little lower than 1980’s 17.8% return, but still a strong showing given the economic headwinds. Over the 17 years since Buffett and his team took over, Berkshire’s book value per share grew from just $19.46 to an impressive $526.02. That’s a compounded annual growth rate of 21.1%. Still, Buffett cautions that it will be harder to maintain such high growth going fo...