RDP 9810: The Distribution and Measurement of Inflation Equation

\begin{array}{l} t \leq k_{1} & j = 1 \\ k_{1} < t \leq k_{2} & j = 2 \\ k_{2} < t \leq k_{3} & j = 3 \\ k_{3} < t & j = 4 \end{array}