The unemployment rate has been crushing the Fed's expectations for years

The unemployment rate has fallen faster and further than anyone reasonably expected.

And this drop has particularly surprised relative to the Fed's outlook, which has been more or less revised lower each quarter over the last several years, only to be bested by the data.

Here's the stunning chart, via Pantheon Macroeconomics.

Pantheon Macroeconomics

As part of its latest monetary policy decision set for release on Wednesday afternoon, the Fed will give its updated outlook on the unemployment rate. In December, the Fed expected the unemployment rate to fall to 5.2%-5.3% by the end of 2015.

In February, the Jobs Report showed that nonfarm payrolls grew by 295,000 while the unemployment rate fell to 5.5%, the lowest since May 2008.

This lead some economists to declare "full employment" as the Fed reaches the upper limit of its "NAIRU" range, or the unemployment rate at which it expects inflation to accelerate.

We'll see what Fed Chair Janet Yellen has to say about that on Wednesday.