user: Question: What is the largest number Lost to David Nalbandian with a Win Rate of 20%?
Columns: ['Opponent', 'Highest ranking', 'Matches', 'Lost', 'Win %']
Types: ['text', 'text', 'real', 'real', 'text']
Sample row: ['Lleyton Hewitt', '1', 2.0, 0.0, '100%']
SQL:

assistant: SELECT MAX("Lost") FROM "Table" WHERE "Win %" = '20%' AND "Opponent" = 'David Nalbandian';