{"pre_text": ["majority of the increased tax position is attributable to temporary differences .", "the increase in 2014 current period tax positions related primarily to the company 2019s change in tax accounting method filed in 2008 for repair and maintenance costs on its utility plant .", "the company does not anticipate material changes to its unrecognized tax benefits within the next year .", "if the company sustains all of its positions at december 31 , 2014 and 2013 , an unrecognized tax benefit of $ 9444 and $ 7439 , respectively , excluding interest and penalties , would impact the company 2019s effective tax rate .", "the following table summarizes the changes in the company 2019s valuation allowance: ."], "post_text": ["included in 2013 is a discrete tax benefit totaling $ 2979 associated with an entity re-organization within the company 2019s market-based operations segment that allowed for the utilization of state net operating loss carryforwards and the release of an associated valuation allowance .", "note 13 : employee benefits pension and other postretirement benefits the company maintains noncontributory defined benefit pension plans covering eligible employees of its regulated utility and shared services operations .", "benefits under the plans are based on the employee 2019s years of service and compensation .", "the pension plans have been closed for all employees .", "the pension plans were closed for most employees hired on or after january 1 , 2006 .", "union employees hired on or after january 1 , 2001 had their accrued benefit frozen and will be able to receive this benefit as a lump sum upon termination or retirement .", "union employees hired on or after january 1 , 2001 and non-union employees hired on or after january 1 , 2006 are provided with a 5.25% ( 5.25 % ) of base pay defined contribution plan .", "the company does not participate in a multiemployer plan .", "the company 2019s pension funding practice is to contribute at least the greater of the minimum amount required by the employee retirement income security act of 1974 or the normal cost .", "further , the company will consider additional contributions if needed to avoid 201cat risk 201d status and benefit restrictions under the pension protection act of 2006 .", "the company may also consider increased contributions , based on other financial requirements and the plans 2019 funded position .", "pension plan assets are invested in a number of actively managed and commingled funds including equity and bond funds , fixed income securities , guaranteed interest contracts with insurance companies , real estate funds and real estate investment trusts ( 201creits 201d ) .", "pension expense in excess of the amount contributed to the pension plans is deferred by certain regulated subsidiaries pending future recovery in rates charged for utility services as contributions are made to the plans .", "( see note 6 ) the company also has unfunded noncontributory supplemental non-qualified pension plans that provide additional retirement benefits to certain employees. ."], "table": [["balance at january 1 2012", "$ 21579"], ["increases in current period tax positions", "2014"], ["decreases in current period tax positions", "-2059 ( 2059 )"], ["balance at december 31 2012", "$ 19520"], ["increases in current period tax positions", "2014"], ["decreases in current period tax positions", "-5965 ( 5965 )"], ["balance at december 31 2013", "$ 13555"], ["increases in current period tax positions", "2014"], ["decreases in current period tax positions", "-3176 ( 3176 )"], ["balance at december 31 2014", "$ 10379"]], "table_ori": [["Balance at January 1, 2012", "$21,579"], ["Increases in current period tax positions", "—"], ["Decreases in current period tax positions", "(2,059)"], ["Balance at December 31, 2012", "$19,520"], ["Increases in current period tax positions", "—"], ["Decreases in current period tax positions", "(5,965)"], ["Balance at December 31, 2013", "$13,555"], ["Increases in current period tax positions", "—"], ["Decreases in current period tax positions", "(3,176)"], ["Balance at December 31, 2014", "$10,379"]]}

Question: by how much did the company 2019s valuation allowance decrease from the beginning of 2012 to the end of 2014?
Evidence:
table_9: balance at january 1 2012 the balance at december 31 2014 of $ 21579 is $ 10379 ;
Program: subtract(10379, 21579), divide(#0, 21579)
Answer:
str_answer: -51.9%
exe_answer: -0.51902