The revised GDP figures were chiefly helped by a boom in the key tourism industry, which accounts for more than 15 percent of the Greek economy and sustains about one in five jobs."The remarkable rise in tourism definitely had an extremely positive effect on the economy," Agapitos said. Tourism officials expect a record 17 million arrivals this year â¿¿ up from 16 million in 2012. Greece's conservative government has promised to balance its annual budget this year, continuing austerity measures including plans to launch a program for mass public sector firings this year. Unions are planning anti-austerity demonstrations over the weekend in Greece's second largest city, Thessaloniki, where conservative Prime Minister Antonis Samaras will open an international trade fair and make an annual address on the state of the nation's economy. More than 4,000 police officers are on duty for the demonstrations. But on Friday, police officers staged their own uniformed demonstration in the northern Greek city against government pay cuts. "Our struggle is to ensure public safety, but also our own survival," Christos Fotopoulos, head of the Greek Police Officers' Association, said. "What they have done to us is degrading and it must stop." __ Costas Kantouris reported from Thessaloniki.