The given graph represents the rainfall (in cm) in a city, over a period of six years. Study the graph and answer the question that follows.

In which two consecutive years was the difference of the rainfall minimum?

2005 - 2006

Difference in rainfall in 2005 and 2006 = 50 - 40 = 10

Difference in rainfall in 2006 and 2007 = 100 - 50 = 50

Difference in rainfall in 2007 - 2008 = 100 - 80 = 20

Difference in rainfall in 2008 - 2009 = 80 - 20 = 60 

Difference in rainfall in 2009 - 2010 = 120 - 20 = 100

Difference in rainfall minimum = 10 cm

For two consecutive years is for  2005 - 2006