Vietnam index up 0.15 pct at midday, strong liquidity

HANOI, Feb 19 (Reuters) - Vietnam's benchmark VN Index inched up 0.15 percent at the break on Wednesday on extended buying demand, with a high trading volume. Petrovietnam Drilling and Well Services Company led the gains, with shares climbing 3.92 percent, followed by food producer Masan Group that advanced 0.54 percent. Volume reached 99 million shares by midday, compared with a five-day average level of 142 million shares, according to Reuters data. Optimism over the macro eco