buenos air argentina congress pass reform pension system tuesday days demonstrations bill opponents violent clash protesters police measure central president mauricio macri plan slash fiscal deficit attract investment pave way market-friendly legislation cambiemos let change coalition hop pass extraordinary congressional sessions end year law change formula use calculate benefit link consumer price instead tax income wage hike government say make benefit predictable sustainable still increase inflation next year formula guarantee next years retire never lose jump inflation say macri take office december 2015 decade populist rule macri tweak proposal pledge one-time bonus payment needy retire clash last thursday derail congressional debate still measure generate fierce criticism opposition lawmakers labor unions say hurt retire debate prompt demonstrations monday thousands take streets capital buenos air around country bang pot pan blare car horn stone-throwing protesters confront police respond water canon rubber bullets tear gas dozens injure change generate discomfort necessary macri say measure pass low chamber deputies 127-117 two abstentions follow all-night debate session senate approve proposal last month government press congressional vote tax code overhaul deal provinces limit spend macri tell reporters economists note inflation expectations low say link benefit consumer price would low spend around 0.5 percent gross domestic product gdp next year save pension reform finance transfer national treasury provinces part fiscal pact say economist ariel barraud argentina fiscal analysis institute cordoba argentina almost save obtain pension formula change go compensate fiscal deal barraud tell reuters phone argentina government aim cut deficit 3.2 percent gdp 4.2 percent currently cambiemos lack majority congress despite strong performance october legislative midterm dozens vote opposition lawmakers need pass pension measure leaders south america hard time implement similar business-friendly agendas peru measure mean boost growth stall president pedro pablo kuczynski fight efforts remove tie scandal-plagued brazilian builder odebrecht brazil efforts pension reform recently push back next year despite passage pension measure macri agenda still face substantial popular skepticism encroach upon right society vulnerable opposition lawmaker facundo moyano say congressional debate argentina congress pass pension reform protest clash