Greek stocks had a bad start to the week yesterday as selling pressure in banks and mid-caps drove the benchmark general index down to just above the 1,800-point support level. The Athens bourse’s benchmark general index gave up 2.86 percent, ending at 1,804.91 points. The blue chip FTSE/ATHEX 20 index fell 2.65 percent to 882.86 points under the weight of a 3.56 percent slide in National Bank which ended at 11.11 euros. Piraeus Bank slumped 5.23 percent to 5.64 euros and power company PPC closed at 12.22 euros, down 4.31 percent. The mid-cap FTSE/ATHEX 40 index retreated 3.67 percent. Steelmaker Sidenor tumbled 12.11 percent to 3.12 euros and construction company Michaniki fell 7.59 percent to 0.73 euros. Turnover reached 186 million euros versus 316 million in the previous session.