Table:
0
A
B
C
D
E
F
1
Year
Stage
Category
Start
Finish
Leader at the summit
2
2013
8
HC
Castres
Ax-3 Domaines
Nairo Quintana ( COL )
3
2010
14
HC
Revel
Ax-3 Domaines
Christophe Riblon ( FRA )
4
2007
14
HC
Mazamet
Plateau-de-Beille
Rubén Pérez ( ESP )
5
2005
14
HC
Agde
Ax-3 Domaines
Georg Totschnig ( AUT )
6
2003
13
1
Toulouse
Ax-3 Domaines
Juan Miguel Mercado ( ESP )

Questions and formulas:
Question: Who was the leader at the summit for the race in 2005?
Formula: UNIQUE(CHOOSECOLS(FILTER(A1:F1,A1=2005),6))
Formula2: UNIQUE(CHOOSECOLS(FILTER(A2:F6,A2:A6=2005),6))
Level: medium
Question: What is the sum of the stages for category 1 races after the year 2003?
Formula: SUM(FILTER(B1, (C1=1)*(A1>2003)))
Formula2: SUM(FILTER(B2:B6, (C2:C6=1)*(A2:A6>2003)))
Level: easy