A Pi Q Q, De Consumer surplus pre-tax is represented by the shaded region (use letter+letter format in alphabetical order, ex: A+B+C). Consumer surplus post-tax is represented by the shaded region AA (use letter+letter format in alphabetical order, ex: A+B+C). It's evident from the graph that this tax is collected from A (consumers/producers). The tax revenue generated by the tax is represented by the shaded region A (use letter+letter format in alphabetical order, ex: A+B+C).