XYZ Corp purchased a vehicle on June 30, 2020 for $20,000 and paid an additional $1,000 to ship the vehicle to their location. The vehicle is esimated to have a $4,000 residual value at the end of its useful life. It is estimated to last for 8 years. Their year-end is Dec 31, 2020. Calculate the depreciation expense using the straight-line method.