What on earth has gone wrong with Japan?
There was not a single Japanese member of the BBC Global 30 that made a gain last month.
Certainly, the US economy is worrying the Japanese. Justin Urquhart Stewart, of Seven Investment Management, believes that has particularly upset the big exporters.
"However," he says, "China has now overtaken the US as Japan's principle export market, and for the medium, mid-sized companies that is where they are worried about a slowdown."
With an 11.1% annual growth rate reported in China in April, that country is roaring ahead.
But the authorities also took another step to rein in lending, and they are determined to do more.
One has an image of China pumping the footbrake, yanking the handbrake and finally hurling an anchor out the back in an attempt to halt this runaway economy. That is what has started the red warning lights to flash in Japan.
Not surprisingly two of China's biggest companies China Mobile (down 0.5%) and the oil producer CNOOC (down 3.5%) were also buffeted by this chill wind.
But it's not as though everything was sweetness and light in Japan's home markets either: deflation is back - for how long no one knows, but with core consumer prices falling for the second consecutive month in the year to March, interest rates won't rise and the banks won't get rich on such lean margins in their lending.
Biggest losers on the BBC Global 30
Mitsubishi UFJ Financial: -8.99%
Seven & I Holdings: -6.67%
Toyota Motor: -6.12%
Tokyo Elec Power: -4.37%
Shares in the country's biggest bank, Mitsubishi UFJ, were the biggest loser on the Global 30 last month, falling 9%.
In the retail sector, Seven & I, which runs convenience outlets, department stores and supermarkets, dropped 7%. Its forecasts for this year's profits are meagre indeed, because, it says, of rising investment costs: investors also remember that it missed its profit targets last year.
Further out, Mr Urquhart Stewart believes China's growth will continue to provide a massive market for Japan, increasingly in consumer goods.
He is far more downbeat on the US.
"It's a question of how low and how slow do we go," he says. "We have a slowing economy there, we have the housing market issues we all know about. The corporate results have been good this last month, but that is historic and backward looking.
"The OECD forward forecasts point to slower growth there and when there is a recovery it will be from a position of weakness."
In Japan, Toyota is the best example of a casualty of the US deceleration.
Biggest winners on the BBC Global 30
Just as one might expect it to be rejoicing at having finally become the world's biggest-selling carmaker, knocking the Americans (and GM in particular) off their perch for the first time in a century, its shares fell 6%.
Its investors are fretting over the strength of the yen against the dollar (it gained 1.7% last month). It matters little if you sell more cars than anyone else, if the dollars you sell them for are falling in value every month.
All the same, the good earnings have kept the US market happy enough: Exelon, the energy group, reported a 73% rise in net income, as electricity prices rose. Its shares are up 8.7% in April.
Microsoft shares are up 5.9% as its earnings rose 65%. Johnson & Johnson shares are up 4.3% as its earnings rose 15% and it promised an increase in its dividend of some 10%.
Even HSBC, which drew global attention to the depth of the US mortgage market problems and which saw a 14% fall in its shares from November to March, finally clawed back 4% in April.
But the star performer on the Global 30 was in Europe.
It seems that there's nothing like a brushing out of dead wood, especially under the spotlight of a financial scandal, to give a share price a boost.
The irony for Siemens, where an investigation into a bribery scandal is underway, is that many would describe the wood as anything but dead.
In fact, Klaus Kleinfeld, the outgoing chief executive, is generally regarded as the architect of Siemens' recovery over the last year. He has cut some 7,000 jobs, sold off large swathes of the business, and spent some $12bn in acquisitions.
The shares are up almost 50% in the last 12 months.
In fact, the final 13% of that gain came in April in reaction to his resignation and the exit of Chairman Heinrich von Pierer. The day after he announced his resignation, Mr Kleinfeld said all the group's business units had met or exceeded profitability targets in the second quarter of the year.
Both Mr Kleinfeld and Mr von Pierer deny any involvement in the bribery scandal.