1. A measuring endoscope apparatus comprising: an imaging element that images a subject to generate image data; a display; a memory which stores first calibration data and second calibration data, the first calibration data being calibration data of a calibrator which is used to calibrate the measuring endoscope apparatus, and the second calibration data being calibration data of the measuring endoscope apparatus; and a controller which is configured to generate measurement data of the subject based on the image data which is obtained by imaging the subject to perform measurement after the first calibration data and the second calibration data have been stored in the memory, and generate an image file to be recorded on a recording medium such that the image file includes the image data, the measurement data, the first calibration data, and the second calibration data, wherein the controller is configured to read the second calibration data from the memory and generate a calibration certificate of the measuring endoscope apparatus, wherein the second calibration data includes a calibration expiry date, wherein the controller is configured to display an alert on the display, when a remaining days until the calibration expiry date are less than a predetermined number days or when the calibration expiry date has passed, and wherein the controller is configured to read the second calibration data from the recording medium and generate an examination report according to a predetermined format based on the measurement data, the image data, and the second calibration data.