Depth of Field - Sensor APS-C?

Can anyone tell me where the SENSOR value at the bottom left of the attached image is set? I have my sensor measurements set to 40mm x 17mm – 2.35 aspect ratio for a typical S35 sensor. The sensor value is reporting APS-C with a 1.6 crop-factor – but that doesn’t make any sense. In real life that crop-factor would impact the focal length but I’m not sure if it impacts the DOF and lens calculations or not.

Changing the size of the sensor doesn’t make a difference. Is there a setting or a mechanism to adjust the sensor and crop-factor?