Tasty Subs acquired a delivery truck on October 1, 2015, for $21,500. The company estimates a residual value of $2,500 and a six-year service life. It expects to drive the truck 100,000 miles. Actual mileage was 5,000 miles in 2015 and 19,000 miles in 2016. Required: Calculate depreciation expense using the activity-based method for 2015 and 2016, assuming a December 31 year-end. (Do not round your intermediate calculations.)