Question:
Who was the head of Hamburg in Aug, 2011?

Context:
 Peter Schulz is the head of the government of Hamburg from Jun, 1971 to Nov, 1974. 
 Hans-Ulrich Klose is the head of the government of Hamburg from Nov, 1974 to May, 1981. 
 Ortwin Runde is the head of the government of Hamburg from Nov, 1997 to Oct, 2001. 
 Carl Vincent Krogmann is the head of the government of Hamburg from Mar, 1933 to May, 1945. 
 Herbert Weichmann is the head of the government of Hamburg from Jun, 1965 to Jun, 1971. 
 Olaf Scholz is the head of the government of Hamburg from Mar, 2011 to Mar, 2018. 
 Kurt Sieveking is the head of the government of Hamburg from Dec, 1953 to Nov, 1957. 
 Rudolf Petersen is the head of the government of Hamburg from May, 1945 to Nov, 1946. 
 Henning Voscherau is the head of the government of Hamburg from Jun, 1988 to Oct, 1997. 
 Paul Nevermann is the head of the government of Hamburg from Jan, 1961 to Jun, 1965. 
 Max Brauer is the head of the government of Hamburg from Nov, 1946 to Dec, 1953. 
 Klaus von Dohnanyi is the head of the government of Hamburg from Jun, 1981 to Jun, 1988. 
 Christoph Ahlhaus is the head of the government of Hamburg from Aug, 2010 to Mar, 2011. 
 Peter Tschentscher is the head of the government of Hamburg from Mar, 2018 to Dec, 2022. 
 Ole von Beust is the head of the government of Hamburg from Oct, 2001 to Aug, 2010.

Answer:
Olaf Scholz