Using the AMORDEGRC function:
The arguments for the AMORDEGRC function are:
Argument  Required?  Description 

cost  Required  The cost of the asset. 
date_purchased  Required  The date of the purchase of the asset. 
first_period  Required  The date of the end of the first period. 
salvage  Required  The salvage value at the end of the life of the asset. 
period  Required  The period. 
rate  Required  The rate of depreciation. 
basis  Optional  The year basis to be used. 
A few more things:
• Excel stores dates as sequential serial numbers so they can be used in calculations. By default, January 1, 1900 is serial number 1, and January 1, 2014 is serial number 41640 because it is 41,640 days after January 1, 1900. 
• The AMORDEGRC function will return the depreciation until the last period of the life of the assets or until the cumulated value of depreciation is greater than the cost of the assets minus the salvage value. 
• The AMORDEGRC function uses a depreciation coefficient that is applied in the calculation depending on the life of the asset: 

• The depreciation rate will grow to 50 percent for the period preceding the last period and will grow to 100 percent for the last period. 
• If the life of assets is between 0 (zero) and 1, 1 and 2, 2 and 3, or 4 and 5, the #NUM! error value is returned. 