<h1>Benchmark indices climb sixth straight day as GST two-slab proposal and sovereign rating upgrade boost investor confidence</h1> Benchmark equity indices rose for a sixth day, with the 30-stock index gaining about 143 points and the 50-stock index up roughly 33 points, driven by buying in major private bank and large-cap energy and financial stocks; market breadth was mixed. Officials' proposal to rationalize the goods-and-services tax into a two-slab structure (5% and 18%) pending final council approval next month and a recent sovereign credit-rating upgrade were cited as confidence drivers. Investors also awaited a key U.S. central bank official's remarks. Foreign institutional investors were net sellers while domestic institutions were net buyers.