PURPOSE: To simply and easily prepare a graph easy to see, and to improve the appealing effect of a text. in a document processor.

CONSTITUTION: This device is equipped with an item data storage means 1 which stores item data, numerical data storage means 2 which stores numerical data, plotting means 3 which plots a graph set by the item data and the numerical data, numerical data display means 4 which displays the numeric value of display data on the graph, and numerical data display position changing means 5 which changes the numerical data displayed by the numerical data display means 4 to an arbitrary position.