Calculate deprecation based on a specific cell value

[Bishop1999]

Ladies and Gentlemen, I have Excel report listing the future value of various assets, from that I seek to calculate the annual depreciation given a .025%. What I seek is assistance with my formula I'm attempting to calculate varying depreciation values based on the age of the asset. Example asset (A) has a purchase price of 12K, a rate of .025 and life expectancy of 12 years. The future value will work if we replaced the asset after 12 years however, we make keep the unit for 14. The last two years should only have the inflation (.025%) how do I address this concern. I have the a sample file with the formula but am unsure how to attach.