Which country's patent is at the beginning of AY?

The beginning of AY may be wrong. The following are all the country codes of patents starting with a that I have found.

Andorra

Ae United Arab Emirates

Af Afghanistan

Ag Antigua and Barbuda

Anguilla

Albania

Am Armenia

Netherlands Antilles

Ao Angola

Ar Argentina

In Austria

Australian Union

Aw Aruba

Az Azerbaijan