Before revision:  Using this simple concept combined with monotonicity of Expected Shortfall with respect to its target confidence level , one can provide an unconditional coverage backtesting framework for Expected Shortfall that is a natural extension of the current Value-at-Risk regulatory traffic-light approach  .
After revision:  Using this simple concept combined with monotonicity of Expected Shortfall with respect to its target confidence level we introduce a natural and efficient backtesting framework. Our test statistics is given by the biggest number of worst realisations for the secured position that add up to a negative total. Surprisingly, this simple quantity could be used to construct an efficient backtesting framework for Expected Shortfall that is a natural extension of the current Value-at-Risk regulatory traffic-light approach .