The UEFA coefficient is a ranking system used by the Union of European Football Associations to evaluate the performance of football clubs and national teams in European competitions. It is calculated based on the results of clubs in tournaments like the UEFA Champions League and UEFA Europa League over a specific period, typically five years. These coefficients help determine seedings for draws and the allocation of spots in European competitions. Higher coefficients indicate better performance, allowing clubs from those countries to gain more favorable positions in tournaments, which can lead to increased revenue and prestige.