Question: What is the name and open year for the branch with most number of memberships registered in 2016?
SQL: SELECT T2.name ,  T2.open_year FROM membership_register_branch AS T1 JOIN branch AS T2 ON T1.branch_id  =  T2.branch_id WHERE T1.register_year  =  2016 GROUP BY T2.branch_id ORDER BY count(*) DESC LIMIT 1