Grove oxygen sensor pro output voltage

Hi,
I have just received the Grove Oxygen Sensor pro (GGC2330-O2). I connected the sensor to an Arduino Mega with +5V and uart. I ran some tests, using the test script on the website.
In the first test i placed the sensor in a room with normal oxygen level, uart showed output 21 % and output voltage (V0) 1.5 V.
I then placed the sensor in an environment with lower oxygen content, the uart then displayed 16 % and V0 was measured to 1.9 V.
According to the datasheet, the output should be between 1.5-0V which seems odd with respect to my tests? Do I misunderstand something?

datasheet

Thanks!

Sorry for the inconvenience, I see that our Wiki example also shows 1.9V, so I’m not sure if there was a labelling error in the document you found. Can you tell me where you found your screenshot? Thank you. If it is the problem, we will fix it as soon as possible.

The datasheet was found under Resources on the wiki site, see link here:
Wiki

The output from the Arduino IDE seems to belong to an old example since the example code just print O2 from uart.

Is the output range 0-25 % and if there is an error in the document, what should the corresponding output voltage be?