The current economic expansion, which is the second-longest the country has experienced since World War II, has been sluggish at best, causing many economists to wonder if a recession is on the horizon.

Peterson Institute for International Economics leader Adam Posen is one such economist. In a recent CNBC interview he said he expects a recession to hit in the next two years as the U.S. economy enters a boom-bust cycle, Bloomberg reports. While President Donald Trump promised to push annual gross domestic product growth to 4%, most economists believe even 3% is unreachable in today’s environment of low unemployment and tepid growth.

That does not mean everyone thinks the U.S. is headed toward disaster. The Federal Reserve raised interest rates in March and will likely raise them at least two more times this year as strong economic factors and rising inflation show the country can support such moves.