stand for totally illiquid pieces of, well, family show.

You'll have to ask a trader.

But regardless, the TIPS market is watched closely as an important signal of expectations, of future inflation.

Because of the price, in which the securities trade relative to upper treasuries.

It's why so many investors and economist, including at the Federal reserve,

which is meeting to decide monetary policy today,

are investigating the same puzzle right now.

Why have expectations for US inflation in the next decade slipped so much?

On its face, this looks a deeply disappointing signal for policy makers.

A suggestion that there are attempts to reflate the economy and to meet their target of stable annual inflation at around 2%

have gone way off track.

Even after a rebound in recent days, the markets implying that inflation in the years from 2021 to 2026 will be down at 1.6%.

Now that suggests that financial markets don't really believe in the Fed's long-term inflation target.

And if that's true, that could have real and immediate consequences.

What people expect inflation to be closely affects what inflation actually turns out to be because it gets baked into the price rise.

Is that the business push through or the wage increases that workers push for?

The Fed thinks that survey-based measures of inflation expectations may be more reliable than anything thrown out by the market.

As policy makers discuss when they last met in January, those surveys show expectations are still anchored higher.

Over late the TIPS markets implied inflation measure with the oil price.

And things become clearer.

Since oil began falling in 2014, there's been a tight correlation between inflation expectations and the crude price.

And while short-term inflation is obviously affected by oil, consumer prices in the next decade shouldn't be.

Oil cannot keep falling forever.

So the more likely solutions of the puzzle is the more sanguine one.

The relatively illiquid TIPS market has been swept up in the speculative drama surrounding the oil price,

and it no longer tells you very much about the long-term inflation expectations.

Stephen Foley for the Financial Times.