future tense - Which sentence is most appropriate? "Next year Anny and I {will have been / will be} married for 25 years"

Which sentence would be most appropriate?

1. 
   

   Next year Anny and I will have been married for 25 years.

   
   


2. 
   

   Next year Anny and I will be married for 25 years.

   
   

(this sentence came out of a grammar book. I had to fill in the gap "Next year Anny and I (to be) married for 25 years.)