user: Question: What percentage of browsers were using Safari during the period in which 31.27% were using Firefox?
Columns: ['Date', 'Internet Explorer', 'Firefox', 'Safari', 'Opera']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['October 2013', '28.96%', '18.11%', '8.54%', '1.20%']
SQL:

assistant: SELECT "Safari" FROM "Table" WHERE "Firefox" = '31.27%';