user: Question: What is the average Year when the Competition was Friendly, and a Club of Everton?
Columns: ['Year', 'Competition', 'Club', 'Nation', 'Result']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [2010.0, 'Preseason', 'Club Universidad de Guadalajara', 'Mexico', 'W 0–1']
SQL:

assistant: SELECT AVG("Year") FROM "Table" WHERE "Competition" = 'Friendly' AND "Club" = 'Everton';