Summary
- The real yield of -0.272% fell about 53 basis points below the yield of the originating auction on February 20.
- Investors had to pay a huge premium to collect the coupon rate of 0.25%, about $116.32 for about $100.26 of inflation-adjusted principal.
- The market reaction to the auction looked negative, with the yield climbing about 6 basis points higher than where this TIPS was trading minutes before the auction close.
The U.S. Treasury’s auction Thursday of $7 billion in a reopened 30-year Treasury inflation Protected Security – CUSIP 912810SM1 – generated a real yield to maturity of -0.272%, the first time in history a TIPS auction of this term resulted in a yield negative to inflation.
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Treasury Inflation-Protected Securities 
Yes, the purchase limit is not affected by an I Bond redemption. It remains $10,000 per person per year.