Table: rail_line_info
Columns: line_name
opened
last_extension
stations_served
length
average_interstation
journeys_made_per_annum

Question: What is the average opened year of line e, which had their last extension before 2003?
SQL: SELECT AVG("opened") FROM rail_line_info WHERE "line_name" = 'line e' AND "last_extension" < 2003