What is the average number of units sold over the years?

Average number of units sold = ( Units sold in 2004 + Units sold in 2005 + Units sold in 2006 + Units sold in 2007 + Units sold in 2008 ) / 5
Average number of units sold = (3.5 + 4 + 5 + 3 + 6.5)/5 = 22/5 = 4.4 crores