Kondratiev wave

Kondratiev waves are big patterns of economic growth and decline. They happen over a long period of time, usually around 50 years. It's like a big roller coaster, except with money and economies instead of riders. It starts out with a period of growth, when businesses can make more money and there are more jobs and more people can buy things. Then, after a while, the growth slows down, and eventually the economy goes into a decline, where money is harder to come by and businesses struggle. Eventually, the decline passes and the economy starts growing again. This is a Kondratiev wave.