user: Question: In 1994 what tournament held a ATP Masters Series
Columns: ['Tournament', '1990', '1991', '1992', '1993', '1994', '1995', '1996', '1997', '1998', 'Career SR']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Grand Slams', 'Grand Slams', 'Grand Slams', 'Grand Slams', 'Grand Slams', 'Grand Slams', 'Grand Slams', 'Grand Slams', 'Grand Slams', 'Grand Slams', 'Grand Slams']
SQL:

assistant: SELECT "1994" FROM "Table" WHERE "Tournament" = 'ATP Masters Series';