14 mins ago – 7.15AM Australian shares are set to open lower, and the currency tumbled anew, after Fitch startled markets with the timing of its decision to downgrade the US. Tech shares pulled back ahead of earnings from Apple and Amazon. The S & P 500 had its worst day since April; technology was the worst performer among the 11 sectors. The VIX surged more than 15 per cent. August is a seasonally slower trading month with many Americans on leave before a new school year begins late in the month or early September. ASX futures were down 60...