( 1 ) increase in valuation allowance related to the generation of tax nols and other deferred tax assets . ( 2 ) decrease in valuation allowance associated with adjustments to certain deferred tax assets and their related allowance . ( 3 ) represents dispositions , revisions and/or foreign exchange rate variances and the effect of statutory income tax rate changes . the united kingdom operations were sold in the fourth quarter of 2018 . the argentina operations were sold in the third quarter of 2016