On January $1,2022,$ the Pronghorn Company ledger shows Equipment $$34,560$ and Accumulated Depreciation $$9,720.$ The depreciation resulted from using the straight$-$line method with a useful life of $10$ years and a salvage value of $$2,160.$ On this date, the company concludes that the equipment has a remaining useful life of only $4$ years with the same salvage value.

Compute the revised annual depreciation.