The British Agricultural Revolution describes a period of agricultural development in Britain between the 16th century and the mid-19th century, which saw a massive increase in agricultural productivity and net output. This in turn supported unprecedented population growth, freeing up a significant percentage of the workforce, and thereby helped drive the Industrial Revolution. How this came about is not entirely clear. In recent decades, historians cited four key changes in agricultural practices, enclosure, mechanization, four-field crop rotation, and selective breeding, and gave credit to a relatively few individuals. However, current thinking suggests that fundamental changes in workforce organization, crops and farming methods were largely responsible. For this reason, historians may argue that there was in fact no "revolution", simply a rapid evolution of methods that led to a sharp rise in productivity.