Calculate depreciation expense per mile under units-of-activity method Sarasota Company purchased a delivery truck for $33,000 on January 1, 2020. The truck has an expected salvage value of $1,680, and is expected to be driven 108,000 miles over its estimated useful life of 10 years. Actual miles driven were 16,000 in 2020 and 11,300 in 2021.