Treasury issues a broad range of debt in different maturities, including 4-week bills and 30-year bonds. Additionally, it provides TIPS, or Treasury Inflation-Protected Securities, whose returns are tied to the inflation rate. If you're concerned about inflation, invest in the iShares TIPA Bond (TIP, $114), an ETF that stocks TIPTS with maturations of eight years or more. When stocks rise strongly, indicates that more optimistic businesses and consumers are borrowing and anticipating more inflation due to high rates of interest for longer periods.