user: Question: What is the lowest year in since that had a transfer fee of € 14m and ended after 2011?
Columns: ['Nat.', 'Name', 'Since', 'Goals', 'Ends', 'Transfer fee']
Types: ['text', 'text', 'real', 'real', 'real', 'text']
Sample row: ['GER', 'Michael Rensing', 2003.0, 0.0, 2010.0, 'Youth system']
SQL:

assistant: SELECT MIN("Since") FROM "Table" WHERE "Transfer fee" = '€ 14m' AND "Ends" > 2011.0;