Let the initial price be 100. The new price becomes 116. To keep the expenditure the same, the reduction in consumption must be equal to the price increase fraction: $$ \text{Reduction } \% = \left( \frac{\text{Increase}}{\text{New Price}} \right) \times 100 $$ $$ \text{Reduction } \% = \left( \frac{16}{116} \right) \times 100 $$ $$ \text{Reduction } \% = \frac{1600}{116} \approx 13.79\% $$