Cash Has Been King: When Does It Pay to Take Duration Risk?

While longer-duration Treasuries historically delivered superior real returns, recent periods have shown Treasury bills outperforming significantly, driven by inverted real yield curves and aggressive monetary policy. This shift highlights a two-factor framework for duration decisions: primarily, the inflation relationship, where positive Treasury bill real yields favor short-term positioning, and secondarily, the yield curve shape, which offers only marginal additional guidance. Currently, with Treasury bills offering approximately 1.23% positive real yields, the strategy favors staying short, but investors should consider extending duration if T-bill real yields turn negative.

Analysis

The historical outperformance of longer-duration Treasuries, with 10-year notes averaging 2.00% annual real returns since 1961 compared to 0.65% for 3-month bills, has significantly reversed in recent years. Over the last three years, 3-month Treasury bills delivered 5.51% real returns, while 10-year notes posted -5.70%, driven by inverted real yield curves and aggressive monetary policy. This shift highlights that the conventional risk-return relationship can break down under specific market conditions.

Real yields are the primary determinant for duration decisions, with recent data showing 3-month bills offering the highest real yields (1.05% over three years) compared to longer maturities (10-year notes at 0.34%). This inverted real yield structure directly explains the superior performance of short-term instruments, indicating that investors are currently better compensated for maintaining short duration.

Inflation dynamics are the dominant factor influencing Treasury bill real returns, with positive returns (0.45%) occurring when T-bill rates exceed inflation and negative returns (-0.11%) when they lag. The shape of the short-end yield curve is a secondary consideration, providing only a modest 6 basis point advantage for T-bills in a normal curve environment and offering no reliable guidance for extending from 3-month bills to 2-year notes.

Currently, Treasury bills offer approximately 1.23% positive real yields, strongly favoring a short-term positioning strategy. However, should the Federal Reserve push T-bill rates into negative real yield territory, potentially due to re-accelerating inflation combined with accommodative policy, investors should consider extending duration to capture potentially higher real yields in longer maturities.

Key Decisions for Investors

• Investors should prioritize short-term Treasury positioning while Treasury bill real yields remain positive, currently at approximately 1.23%.
• Closely monitor inflation expectations and Federal Reserve policy, as a shift to negative real yields on Treasury bills would necessitate considering extending duration to capture higher real yields in longer maturities.
• Recognize that the shape of the short-end yield curve offers only marginal additional support for T-bills and should not be the primary driver for extending from 3-month to 2-year notes.