LONDON (Reuters) - Following are five big themes likely to dominate thinking of investors and traders in the coming week and the Reuters stories related to them.

FILE PHOTO: Traders work on the floor at the New York Stock Exchange (NYSE) in New York, U.S., April 4, 2019. REUTERS/Brendan McDermid/File Photo

1/BRACE, BRACE

The focus is on the hotly anticipated U.S. results: First-quarter earnings for S&P 500 companies are expected to fall 2.5 percent on the year in what would be the first quarterly decline since 2016. But revenue is expected to rise 4.8 percent.

Those earnings will be crucial to see if the bull market can keep running. Some have argued the Federal Reserve’s patience on rate increases this year as well as stock buybacks will add fuel to the S&P’s rally. Also boosting the S&P 500 Index are the recent performance of the banks and financials, which had suffered more than the broader market in the fourth quarter, when recession fears scared investors away.

First out of the blocks was JPMorgan, which reported a better-than-expected quarterly profit as higher interest income and gains in its advisory and debt underwriting business offset weakness in trading.

Bank of America, Bank of New York Mellon, Goldman Sachs and Morgan Stanley are all scheduled to release their results in days to come. Large banks have indicated that muted capital market activity at the start of the year caused by sluggish trading volumes will be a drag on overall results. Financials are expected to deliver 1.8 percent earnings growth, according to I/B/E/S Refinitiv.

Share performance may boil down to valuation. For the next 12 months, Goldman Sachs appears the cheapest, with investors paying $8.30 for every dollar in expected earnings, compared with $11.80 for Bank of New York Mellon. The former is the worst-performing stock over the last two years among U.S. banks.

For a graphic on First-Quarter Earnings, see - tmsnrt.rs/2D73sU4

2/ARE YOU OK?

April manufacturing activity data will give a glimpse of the economic health of the United States and the euro zone. Chinese GDP data will provide an update on the health of the world’s second-largest economy.

Dismal March PMIs for the United States and euro zone sent shivers through markets. They were taken as ominous signs for the global economy as international trade tensions hurt factory output.

But robust factory data from Beijing offered hope that efforts to shore up China’s economy are kicking in, which injected further fuel to the global equity rally.

The IHS Markit flash Purchasing Managers’ Index due on April 18 should indicate if that optimism was justified -- and if stocks have further upward momentum. China’s first-quarter GDP data is out on April 17.

Many investors say low expectations for first-quarter earnings, dovish central bank policies and hopes for Chinese stimulus and a trade truce between Washington and Beijing are largely priced into equity markets. With all that baked in and investors still scrambling for consensus on what happens over the rest of 2019, there’s a lot riding on that data.

For a graphic on PMI services, see - tmsnrt.rs/2X3sX04

For a graphic on PMI manufacturing, see - tmsnrt.rs/2VEEWR9

3/TRY-ING TIMES

For all the relief in emerging markets that the Federal Reserve doesn’t expect to raise interest rates anytime soon and that commodity prices are hot again, there are still the troublesome twosome: The Turkish lira and Argentine peso.

The peso has slumped to fresh lows in the past 10 days, although the International Monetary Fund’s unlocking a $10.8 billion tranche of funds helped the battered currency to regain some of its footing.

Meanwhile, nine weeks of losses in the last 10 have the lira sliding back toward six to the dollar, the level that set alarm bells ringing last year.

Ankara’s economic reform plans -- announced on Wednesday -- failed to impress markets and investor meetings with Finance Minister Berat Albayrak at the IMF and World Bank spring meetings did little to change that. Ankara’s row with Washington over plans to buy a Russian missile defense system and declines in its FX reserves have only added to the concern of investors still smarting from last month’s pre-election move to temporarily freeze the London lira market.

For a graphic on Lira volatility, see - tmsnrt.rs/2X4U1vO

4/POLLS, PINS AND NEEDLES

The world’s largest and third-largest democracies are going to the polls. Indonesia holds parliamentary and presidential elections on April 17. India’s elections are spread over seven phases and 39 days.

Both countries face similar issues around anti-incumbency and flailing economic growth. Betting on continuity, investors have pumped money into their markets, driving up bonds and stocks.

Polls in Indonesia suggest President Joko Widodo, or Jokowi, who faces his opponent from 2014 once again, will not only win re-election but will also emerge with a stronger coalition. Indonesian markets have also always scored well in election years.

So it’s India that investors should be sweating over. Even if the February tensions with neighbor Pakistan have given Prime Minister Narendra Modi and his coalition an edge, the risks are that he will lose his majority and may cobble together a new partnership that could slow down reforms.

For a graphic on JKSE in election years, see - tmsnrt.rs/2CFzUMY

5/TRUNCATED TRADING

It’s the start truncated trading - the first of four consecutive shortened trading weeks, as a series of public holidays in Europe begins with Easter. Japanese markets will also be closed for a string of holidays in late April.

The truncated weeks come just as volatility in financial markets has slumped. In equities, the VIX, known as the “fear index”, is close to its lowest levels since October. Foreign exchange price swings have fallen to their lowest for several years, according to the Deutsche Bank Currency Volatility Index.

Even the British pound, long the vent for Brexit-related angst, has turned increasingly calm -- and traders are not expecting many big moves for sterling in the months ahead after this week’s six-month Brexit delay.

Caught between mixed economic data releases of recent weeks, a postponement to figuring out how Britain will extricate itself from the European Union until as late as October and elusive progress in the Sino-U.S. trade war have left markets treading water.

But with fewer traders at their desks on fewer days, the rest of April will see heightened risks of a spike in volatility, or even flash crashes, should a surprise hit markets just as calmness descends.

For a graphic on Market volatility, see - tmsnrt.rs/2DaIljM