deletions | additions       diff --git a/tax system 1970-1974.md b/tax system 1970-1974.md  index 5396022..4d93891 100644  --- a/tax system 1970-1974.md  +++ b/tax system 1970-1974.md 
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In 1972 severl important modification to sales-and-buying? tax were enacted.  1. March 1971, the exempt trench of CGT rose from one to two annual vital wages  2. November 1972, 1972: Labor Rents Tax (Impuesto Unico a las Rentas del Trabajo) replaces dual taxation system (second category tax besides CGT) , resulting in lower tax loads for taxpayers, specially those with low labor earnings. This tax was similar in progresiveness and thresholds to the CGT.  bla