Yellen: Expect Rate Hike in 2015, Several Years before Fed Funds Rate "back to normal" level

From Fed Chair Janet Yellen: The Outlook for the Economy

[I]f the economy continues to improve as I expect, I think it will be appropriate at some point this year to take the initial step to raise the federal funds rate target and begin the process of normalizing monetary policy. To support taking this step, however, I will need to see continued improvement in labor market conditions, and I will need to be reasonably confident that inflation will move back to 2 percent over the medium term.

After we begin raising the federal funds rate, I anticipate that the pace of normalization is likely to be gradual. The various headwinds that are still restraining the economy, as I said, will likely take some time to fully abate, and the pace of that improvement is highly uncertain. If conditions develop as my colleagues and I expect, then the FOMC's objectives of maximum employment and price stability would best be achieved by proceeding cautiously, which I expect would mean that it will be several years before the federal funds rate would be back to its normal, longer-run level.

Having said that, I should stress that the actual course of policy will be determined by incoming data and what that reveals about the economy. We have no intention of embarking on a preset course of increases in the federal funds rate after the initial increase. Rather, we will adjust monetary policy in response to developments in economic activity and inflation as they occur. If conditions improve more rapidly than expected, it may be appropriate to raise interest rates more quickly; conversely, the pace of normalization may be slower if conditions turn out to be less favorable.
emphasis added