Goldman Sachs researchers have been hitting the history books again, trying to divine what happens to currencies when economies stagnate. Answer:  Not as much as you might think

Looking at exchange rates for years before and during “stagnation”, Goldman found that year-to-year FX volatility in such periods is lower than in normal periods. But a lot of it depends on the type of stagnation.

The U.S. earnings season is over bar a handful of firms. It has been robust to say the least: Thomson Reuters Proprietary Research calculates that S&P 500 companies overall had second-quarter earnings growth of 38.4 percent. That was 11 percentage points higher than people had been expecting heading into the season.

There may be more surprises ahead — although which sort, remains in question. The research suggests that analysts still expect solid growth in the coming quarters and that the decline in U.S. economic strength over the summer has not changed their minds much.