Context: Southampton City Council consists of 48 councillors, 3 for each of the 16 wards. Council elections are held in early May for one third of the seats (one councillor for each ward), elected for a four-year term, so there are elections three years out of four. Since the 2015 council elections, the composition of the council is:

Question: How many concillors sit on Southampton's City Council?
Answer: 48

Question: How man wards are there in Southampton?
Answer: 16

Question: How many councillors are assigned to each ward in Southampton?
Answer: 3

Question: In what month are council elections held?
Answer: May

Question: In how many years of every four is a council election held in Southampton?
Answer: three