SELECT YEAR FROM festival_detail WHERE LOCATION  =  'United States' INTERSECT SELECT YEAR FROM festival_detail WHERE LOCATION != 'United States'
In which year are there festivals both inside the 'United States' and outside the 'United States'?
SELECT YEAR FROM festival_detail WHERE LOCATION = 'United States ' INTERSECT SELECT YEAR FROM festival_detail WHERE LOCATION ! = 'United States '
select year from festival_detail where location = value intersect select year from festival_detail where location ! = value
In which year are there festivals both inside the 'United States ' and outside the 'United States ' ?