" In Kondratieff’s theory, each long cycle has an upswing lasting about twenty-five years, fuelled by the deployment of new technologies and high capital investment; then a downswing of about the same length, usually ending with a depression. In the ‘up’ phase, recessions are rare; in the ‘down’ phase they are frequent. In the up phase, capital flows to productive industries; in the down phase it gets trapped in the finance system. "

― Paul Mason , Postcapitalism: A Guide to Our Future