(In 2nd paragraph, corrects to highest since October 2011 not highest in a year)
NEW YORK, June 22 (Reuters) - The U.S. Treasury Department on Thursday sold $5 billion of 30-year Treasury Inflation Protected Securities to robust investor demand, resulting in a yield of 0.880 percent, lower than what traders had expected, Treasury data showed.
The ratio of bids to the amount of 30-year TIPS offered was 2.83, which was the highest since October 2011. The ratio was 2.25 at the prior 30-year TIPS auction in February. (Reporting by Richard Leong; Editing by Dan Grebler)