The
Arduino Micro hardware page states:
Analog Inputs: A0-A5, A6 - A11 (on digital pins 4, 6, 8, 9, 10, and 12). The Micro has a total of 12 analog inputs, pins from A0 to A5 are labelled directly on the pins and the other ones that you can access in code using the constants from A6 trough(sic) A11 are shared respectively on digital pins 4, 6, 8, 9, 10, and 12.
The pinout diagram however shows A0..A7 A9..A12 (A8 missing, A12 added). It seems that the pinout diagram is wrong?

You are right!
Comparing the schematics of "Arduino Micro" and "Leonardo Rev3b"
shows that the text is correct and the pinout diagram is bad:
- A12 should be replaced by A7.
- A7 should be replaced by A8.
You get the simple numbering from A0 to A11, as described in the text and as used by the Leonardo.
Bernt