Warren Buffett's 2011 Shareholder Letter

Excerpt:

Investments that are denominated in a given currency include money-market funds, bonds, mortgages, bank deposits, and other instruments. Most of these currency-based investments are thought of as “safe.” In truth they are among the most dangerous of assets. Their beta may be zero, but their risk is huge.

Over the past century these instruments have destroyed the purchasing power of investors in many countries, even as the holders continued to receive timely payments of interest and principal. This ugly result, moreover, will forever recur. Governments determine the ultimate value of money, and systemic forces will sometimes cause them to gravitate to policies that produce inflation. From time to time such policies spin out of control.

Even in the U.S., where the wish for a stable currency is strong, the dollar has fallen a staggering 86% in value since 1965, when I took over management of Berkshire. It takes no less than $7 today to buy what $1 did at that time. Consequently, a tax-free institution would have needed 4.3% interest annually from bond investments over that period to simply maintain its purchasing power. Its managers would have been kidding themselves if they thought of any portion of that interest as “income.”

For tax-paying investors like you and me, the picture has been far worse. During the same 47-year period, continuous rolling of U.S. Treasury bills produced 5.7% annually. That sounds satisfactory. But if an individual investor paid personal income taxes at a rate averaging 25%, this 5.7% return would have yielded nothing in the way of real income. This investor’s visible income tax would have stripped him of 1.4 points of the stated yield, and the invisible inflation tax would have devoured the remaining 4.3 points. It’s noteworthy that the implicit inflation “tax” was more than triple the explicit income tax that our investor probably thought of as his main burden. “In God We Trust” may be imprinted on our currency, but the hand that activates our government’s printing press has been all too human.

High interest rates, of course, can compensate purchasers for the inflation risk they face with currency-based investments – and indeed, rates in the early 1980s did that job nicely. Current rates, however, do not come close to offsetting the purchasing-power risk that investors assume. Right now bonds should come with a warning label.

Under today’s conditions, therefore, I do not like currency-based investments. Even so, Berkshire holds significant amounts of them, primarily of the short-term variety. At Berkshire the need for ample liquidity occupies center stage and will never be slighted, however inadequate rates may be. Accommodating this need, we primarily hold U.S. Treasury bills, the only investment that can be counted on for liquidity under the most chaotic of economic conditions. Our working level for liquidity is $20 billion; $10 billion is our absolute minimum.

Beyond the requirements that liquidity and regulators impose on us, we will purchase currency-related securities only if they offer the possibility of unusual gain – either because a particular credit is mispriced, as can occur in periodic junk-bond debacles, or because rates rise to a level that offers the possibility of realizing substantial capital gains on high-grade bonds when rates fall. Though we’ve exploited both opportunities in the past – and may do so again – we are now 180 degrees removed from such prospects. Today, a wry comment that Wall Streeter Shelby Cullom Davis made long ago seems apt: “Bonds promoted as offering risk-free returns are now priced to deliver return-free risk.”