a TR information is available from both types of diagrams but it comes in different ways for a demand curve diagram the tr associated with any particular output level is given by the area of the appropriate rectangle for a tR type diagram, the tR value for any output level is given simply by the height of the curve at that output level❑ TR information is available from both types of diagrams but it comes in different ways : ◼ for a demand curve diagram , the TR associated with any particular output level is given by the area of the appropriate rectangle ; ◼ for a TR type diagram , the TR value for any output level is given simply by the height of the curve at that output level