Table:
0
A
B
C
D
E
F
G
1
Date Final
Tournament
Commercial Name
Category
Prize Money/ Surface
Final Match
Semifinal Matches
2
Mar 3
Houston , USA
WCT Houston Shoot-Out
Nabisco Grand Prix
$300,000 Carpet
John McEnroe d. Kevin Curren , 7–5, 6–1, 7–6
John McEnroe d. Peter Fleming , 6–4, 6–0
3
Mar 3
Houston , USA
WCT Houston Shoot-Out
Nabisco Grand Prix
$300,000 Carpet
John McEnroe d. Kevin Curren , 7–5, 6–1, 7–6
Kevin Curren d. Shahar Perkiss , 6–2, 6–2
4
April 14
Dallas , USA
Buick WCT Finals
Nabisco Grand Prix
$500,000 Carpet
Ivan Lendl d. Tim Mayotte , 7–6, 6–4, 6–1
Ivan Lendl d. Jimmy Connors , 6–3, 2–1 ret.
5
April 14
Dallas , USA
Buick WCT Finals
Nabisco Grand Prix
$500,000 Carpet
Ivan Lendl d. Tim Mayotte , 7–6, 6–4, 6–1
Tim Mayotte d. Joakim Nyström , 6–4, 4–6, 6–2, 7–5
6
April 28
Atlanta , USA
WCT Atlanta
Nabisco Grand Prix
$300,000 Carpet
John McEnroe d. Paul Annacone , 7–6, 7–6, 6–2
John McEnroe d. Mike Leach , 6–3, 6–3
7
April 28
Atlanta , USA
WCT Atlanta
Nabisco Grand Prix
$300,000 Carpet
John McEnroe d. Paul Annacone , 7–6, 7–6, 6–2
Paul Annacone d. Kevin Curren , W/O
8
May 12
Forest Hills , New York , USA
Shearson Lehman Brothers Tournament of Champions
Nabisco Grand Prix
$500,000 Clay (Har-Tru)
Ivan Lendl d. John McEnroe , 6–3, 6–3
Ivan Lendl d. Aaron Krickstein , 6–1, 2–6, 6–1

Questions and formulas:
Question: Who played in the semi finals matches at the Buick WCT finals?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:G1,C1="Buick WCT Finals"),7))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:G8,C2:C8="Buick WCT Finals"),7))
Level: medium