Greece is threatening to outlast the forecasts of economists from Nouriel Roubini to those at Citigroup and Capital Economics, rewarding investors who wagered on the sanctity of the euro-area.

Having spent 2012 viewing Greece’s departure from the single currency as impending, forecasters now say it may be two years away or may never happen.

After once assuming a rupture by January, 1 2013, Citigroup has reduced the probability to 60 per cent in the next 18 to 24 months. Roubini, who predicted the 2008 financial crisis, puts the risk at less than 50 per cent.

Upending their prognosis of doom and allowing Greek bonds to be the world’s best performers this year: Election-bound German Chancellor Angela Merkel softened her stance toward Greece, the European Central Bank pledged a souped-up rescue effort and Prime Minister Antonis Samaras delivered on austerity commitments in Athens.

Still, stacked against the country is an outlook plagued by recession and debt.

‘‘We penciled in a Greek exit perhaps in 2012 about a year ago and always conceded it was subject to a lot of uncertainty,’’ said Ben May, a London-based economist at Capital Economics. ‘‘A stable pro-bailout government remained in place and there was a greater willingness among core policy makers to make concessions.’’

Bond investors who ignored euro-breakup predictions were handsomely rewarded in 2012, with Greek securities returning 85 per cent, the highest return among indexes compiled by Bloomberg/EFFAS.

Bets made at Intrade.com suggest a 20.5 per cent chance of a split in the 17-nation currency by December 2013 compared with 63 per cent in May.

Crisis respite

Greece ends the year enjoying some respite from its three-year crisis after it obtained 240 billion euros ($316 billion) of loan pledges, conducted the biggest ever writedown of privately held debt and stuck to its budget-cutting course in the face of an anti-austerity backlash in mid-year elections.

That’s pushed Greek 10-year yields below 13 per cent from a peak of more than 35 per cent before the March restructuring.

Such shifts are prompting economists to rethink their assessment that Greece’s days in the euro were numbered, either because other members would eject the nation or because it would seek the relief of devaluation.

In February, Citigroup economists led by Willem Buiter in London said the possibility Greece would leave the euro area in the next 18 months had increased to 50 per cent from between 25 to 30 per cent, arguing the willingness of creditors to support the country had ‘‘fallen substantially.’’

They increased the risk to 75 per cent in May and by July were citing a 90 per cent chance of departure and identifying January 1 as high noon, while saying it was not a forecast of a precise date.

Abandoning CallCapital Economics, which won the 250,000-pound Wolfson Economics Prize this year for proposing a contingency plan for the breakup of the euro area, was even more aggressive. It ended 2011 with a ‘‘central assumption’’ that Greece would finish this year outside the bloc.

It said in a November 12 report it was ‘‘throwing in the towel’’ on that call, while adding its economists ‘‘still envisage a limited euro-zone break up, probably commencing in 2013 with the exit of Greece.’’

Roubini, co-founder of New-York-based Roubini Global Economics, said December 6 the probability of Greece leaving the euro region is now less than 50 per cent albeit ‘‘meaningful.’’

Two months earlier, Megan Greene, the firm’s director of European economics, said there was a 90 percent chance of a Greek exit in 2013. In February, Roubini told the Athens-based Kathimerini newspaper there was a ‘‘strong chance’’ Greece would surrender the euro in 2013, saying devaluation was the only way to restore economic growth.

Among the factors that have changed is a moderation in the approach of policy makers in northern Europe after their austerity prescriptions failed to pull Greece out of its plunge and pushed the rest of the region into a double-dip recession.

Fighting collapse

Merkel, who faces federal elections next year and writes the brunt of the bailout checks, visited Athens for the first time in five years in October and said she wanted Greece to remain in the euro. A week later, she said Greece’s economic overhaul was taking hold and Germans should restrain finger-pointing at weak neighbors.

‘‘A disorderly collapse of the euro zone is not in anybody’s interest,’’ Roubini said December 6 in Berlin.

At the same time, Samaras has won praise for delivering the budget measures creditors ordered by securing parliamentary support for a batch of pension, wage and benefit cuts in November.

The result of movement on both fronts: a bailout deal in which governments agreed to cut the interest rates on rescue loans, suspend interest payments for a decade and give the nation more time to repay while Greece vowed to engineer a bond buyback.

‘‘Clearly the new Greek government was able to convince others that they’re willing to implement reform,’’ said Juergen Michels, chief euro-area economist at Citigroup in London.

The change in sentiment is reflected in the quarterly Bloomberg Global Poll of investors, analysts and traders who are Bloomberg subscribers. Fifty-seven per cent of those surveyed in May said one or more nations would leave the euro in 2012. Only 30 per cent said the same for 2013 in November.

'Pie in the sky'

For all the aid, Greece has experienced 17 straight quarters of economic contraction and its unemployment rate is at a record 26 per cent, while the median forecast of analysts surveyed by Bloomberg News points to the recession continuing through 2014. Capital Economics says such a backdrop means a debt target of 124 per cent of gross domestic product by 2020 is ‘‘pie in the sky’’ without another default.

‘‘We still view the debt profile as unsustainably high and conditional on over-optimistic forecasts that won’t be met,’’ said May. ‘‘What we’ve seen is pushing the problem a bit further down the road, it doesn’t solve the fundamental problems.’’

Roubini says guaranteeing Greek membership of the euro will require governments such as Germany’s to go even further in nursing the country through decades of austerity, probably by embracing a transfer union in which the rich aid the poor.

‘‘If you’re willing to do that for the sake of keeping the euro zone together then Greece has a chance,’’ he said.

Bloomberg