Conditional graphbar colors


I am trying to create a chart where column B depicts numbers for 2014 and Column c for 2015. 2014 is a line graph and 2015 is a bar graph, I wanted a formula where I can show that everytime value in 2015 is less than 2014 its green and everytime its over, it is red.
For ex week 1 in 2014 is 7 and week 1 in 2015 is 11, so the bar graph for 2015 will show red on top and green below; or if thats not possible, all red.

Hope that makes sense and an excel wiz can help me with this answer.