Mechanic

I know that. But base on what you are saying, we are only counting from 2008 to 2010.
The question specifically stating “Over relevant period from 2008 to 2011”, so it actually means from beginning of 2008 to ending 2010?
See, from
beginning 2008 to ending 2008 —-1
beginning 2009 to ending 2009 —-1
beginning 2010 to ending 2010 —-1
beginning 2011 to ending 2011—–1
Total —————————————-4