A government bond seems the opposite of a stock chart — but a bond's PU (Unit Price) moves every day, forms trends, makes pullbacks, and responds to technical analysis like any price series. This guide explains the mechanics you need to master before looking at the app's Bonds Brasil tab.
A fixed-rate bond promises to pay a fixed amount at maturity (R$ 1,000, by convention). What you trade today is the discount on that amount. If the rate demanded by the market rises, the same future bond is worth less today (larger discount) — the PU falls. If the rate falls, the PU rises. It's an exact seesaw: there's no such thing as rates rising with prices rising.
Duration is the sensitivity of the PU to 1 percentage point changes in the rate. A short-term bond (matures in 1–2 years) swings little; a long-term bond (2045, 2060) swings a lot — in our survey, an IPCA+ 2045 moves about 7× more per rate variation than an IPCA+ 2026. Practical consequence: a long-term bond is fixed income in name, but behaves like a risk asset on the chart — and that's precisely why you can apply swing trade to it.
| Bond | Yield | PU Behavior |
|---|---|---|
| Tesouro Selic | Selic + small spread | Almost a straight line going up — floating-rate bonds have no significant seesaw effect. It's the "cash" of the Investment Clock. |
| Tesouro Prefixado | contracted fixed rate (e.g., 14% p.a.) | Pure seesaw with interest rate expectations. Directional bet on future Selic rate drops. |
| Tesouro IPCA+ | inflation + real interest (e.g., IPCA + 7%) | Seesaw with real interest. Protects against inflation and still fluctuates with the cycle — long maturities are the most volatile in the family. |
| With semi-annual interest | same as above, paying coupon every 6 months | Same logic, slightly shorter duration (you receive part earlier). |
If you hold the bond until maturity, you receive exactly the contracted rate — the interim fluctuation is cosmetic. But if you intend to sell earlier, mark-to-market is your exit price: buying a long-term fixed-rate bond on the eve of an interest rate hike cycle can mean months in the red. This is where technical analysis helps: PU trend, supports, and reading the Investment Clock (reflation favors bonds) tell you if the wind is in your favor.