How BYD disrupted Singapore’s car market – and why the strategy is turning on itself

ECONOMISTS use the term “four-firm concentration ratio”, or C4, to describe the combined market share of the top four companies in an industry.

Why does it matter? Because market share distributions shape how companies compete, and how much they can expect to earn.

When C4 is high and stable, competition is gentle and margins are comfortable. When C4 falls, competition intensifies and profits follow it down. C4 also tells you, if you read it the way BYD does, where the next disruption will come from.