I will point out that Jens Christensen estimates:

The recent economic slowdown has raised concerns about the possibility of sustained deflation in the years ahead. However, a refined model of inflation-indexed and non-indexed Treasury bond yields, which captures accurately the possible inflation outcomes perceived by bond investors, suggests that the probability of sustained deflation is just 5.3%. The model accounts accurately for the behavior of inflation-protected Treasury bond yields during the financial crisis and could prove reliable in evaluating deflation risk.]]>