Distrbute percentage over month

Hello,

I would like to distribute the percentage equally over month period in this table.

As  you see the Target Achieved percentage is calculated as how many vehicles are sold. I would like the percentage ratio colourized at red or green depending on how many days are left in a month. e.g., if their are 20 days remaining the target should be red if below say 25% and should be green if it is above or at 25% or if say there are 15 days remaining then target should be 50% and if it is below 50% then the cell becomes red, and if it at or above 50% then it should automatically cell should turn green.