PURPOSE: To read the timing of less-risk and efficient investment on a graph, by representing graphically the price of convertible debenture while comparing it with an investment estimated value and a parity price.

CONSTITUTION: A (parity price ÷ investment estimated value) 5 is graphed on the X axis, and a (convertible debenture price ÷ investment estimated value) 6 on the Y axis respectively. A straight line 7(Y=X) shows (parity price = convertible debenture price). The minimum price of convertible debenture, however, is equal to the investment estimated value actually, so Y=1 is considered to be the minimum value on the Y axis, so that while Y≤1 is discarded on the Y axis, a (convertible debenture price ÷ investment estimated price -1)8 is shown graphically on the Y axis. The left-to-right movement of the graph means an increase in parity price, and the down-to-up movement an increase in convertible debenture. For safety, comparison with values on the X axis is made, and for efficiency, comparison with a straight line 9(Y=X-1) is made.