Conversation so far:
When did Shinee debut with their first release?
On May 22, 2008, the group's first EP, Replay, was released.
How well did Shinee's Replay EP do?
The group's Replay debuted at number ten on the Korean music charts and peaked at number eight, selling 17,957 copies in the first half of 2008.
What was the name of Shinee's debut album?
The Shinee World is the first Korean language studio album recorded by South Korean boy band, Shinee.
Did Shinee tour or play anywhere following The Shinee World album release?
On December 26, 2010, Shinee commenced their first concert tour, Shinee World, at Yoyogi National Gymnasium in Tokyo.

Question: How many people attended?
Self-contained rewrite: How many people attended Shinee's 2010 concert at Yoyogi National Gymnasium?