but Mexico is beginning to look like a worry.

Donald Trump has just announced tariffs aimed mainly at China and South Korea,

but it is Mexico, which trades more than 80% of its exports to the US,

that is particularly vulnerable to trade tensions.

So why is the Mexican Peso the second best currency performer of the year?

Do investors think those old Donald Trump threats to build that famous border wall

and tear up the North American Free Trade Agreement are just bluff?

NAFTA renegotiation talks resumed on Sunday and there are reasons for investors to bet against their collapse,

not least the risk to US jobs.

But, with a presidential election in Mexico due in July,

those talks could last most of the year.

That election, however, has its own risks.

The end of NAFTA and victory for populist candidate, Andres Manuel Lopez Obrador,

who leads in the opinion polls could send the Peso toward record lows.

And there are ripple effects.

One analysts says China and other Asian countries benefit from NAFTA by exporting products to Mexico,

that are then exported to the US.

So the US now wants amendments that would require at least half of vehicle parts to come from America.

Investors flip-flopped in 2017 on the Peso,

a currency which moved by at least 1% in either direction on 36 days in the last 12 months.

Another big move lower came on Tuesday.

Get used to Peso volatility.