What is the most expensive magazine subscription?

I'm curious, what is the most expensive magazine subscription currently available on the market? Are there any publications that cater to a niche audience or offer exclusive content that justifies their steep subscription prices? It would be interesting to know if there's a specific magazine that stands out as the most luxurious or exclusive subscription option for readers. Additionally, I'm wondering if the cost of these subscriptions is influenced by factors such as the frequency of publication, the quality of the content, or the exclusivity of the materials included.