Martinez, Inc. acquired a patent on January 1, 2017 for $40,000 cash. The patent was estimated to have a useful life of 10 years with no residual value. Amortization is calculated on a straight-line basis similar to depreciation calculations. On December 31, 2018, before any adjustments were recorded for the year, management determined that the remaining useful life was 6 years (with that new estimate being effective as of January 1, 2018). On June 30, 2019, the patent was sold for $25,000. Compute the amount of amortization that would be recorded in 2018.