Extract D states: 'Throughout the mid-20th century, the state-owned railway network, RailNational, operated as the sole employer of certified track-signal engineers, creating a monopsonistic labor market that significantly restricted employment and kept wage rates low.'
With the help of a diagram, explain how a monopsonistic employer like RailNational can lead to lower wages and lower employment levels for specialist track-signal engineers than would exist in a competitive labor market.
