What are the GDP and population of the city that already served as a host more than once?
SELECT t1.gdp ,  t1.Regional_Population FROM city AS T1 JOIN hosting_city AS T2 ON T1.city_id  =  T2.host_city GROUP BY t2.Host_City HAVING count(*)  >  1
SELECT t1.gdp ,  t1.Regional_Population FROM city AS T1 JOIN hosting_city AS T2 ON T1.city_id  =  T2.host_city GROUP BY t2.Host_City HAVING count(*)  >  1
[{'GDP': 614.55, 'Regional_Population': 8004680}]