New numbers from Greece show once again that austerity is a foolish prospect in the middle of a global economic slowdown, as it takes away demand when governments should be fueling it.

Greece’s economy will shrink by more than 5 percent this year, topping earlier projections, the country’s finance minister told business people in this northern Greek city where the prime minister will speak about the economy later on Saturday.

A deep recession is making it harder for Athens to increase tax revenue and meet deficit-reduction goals under a bailout plan agreed to with its euro zone partners and the International Monetary Fund. Without corrective action the continued flow of aid may be at risk.

“The recession is exceeding all projections, even the troika’s forecast,” the finance minister, Evangelos Venizelos, said, referring to the European Union, the International Monetary Fund and the European Central Bank. “The projection in May was that recession would be at 3.8 percent, now we are exceeding 5 percent.”

The Greek economy shrank at an annual 7.3 percent clip in the second quarter, after an 8.1 percent contraction in the first three months of 2011.

Austerity measures, including higher indirect taxes and cuts in public sector pay and pensions, have hurt economic activity.

Despite these near-depression numbers, Greece continues to announce more and more ways to take money out of the economy. The latest is a property tax levy that will be appended to electricity bills.

So the pattern is this. The global economy lurches into crisis. Greece, saddled with debt problems, decides to cut its budget. As a result they sink into near-depression, increasing their own budget deficit. Then they look for more ways to contract.

The answer for Greece is to exit the euro and devalue their currency. Yet this is exactly what their Prime Minister won’t countenance. So more pain and suffering is inflicted on the Greek people, because of a mixture of stubbornness and perceived prestige.

About the only hope for Greece is if Europe up and kicks them out of the economy. That would be a boon to the Greek public, 20,000 of whom protested Prime Minister Georges Papandreou’s speech yesterday. Of course, for Europe to make a decision that has more than a short-term outlook and isn’t inadequate to the task of fixing the problem would be highly out of character as well.