What is the number 1 rarest dog?

In the realm of cryptocurrency and finance, we often delve into matters of scarcity and rarity. However, let's divert our attention momentarily to an unconventional yet intriguing question: "What is the number 1 rarest dog?" This inquiry begs for a meticulous examination of various dog breeds, their global populations, and the rarity of their occurrence. Could it be a rare and endangered breed, such as the Chinese Crested Dog or the Xoloitzcuintli? Or perhaps it's a breed that is so specialized and little-known that it's only found in a remote part of the world. As a questioner, I'm eager to uncover the answer to this unique query, and I hope to gain a deeper understanding of the rarity of dog breeds and their conservation status.