The consumer price index posted a unexpectedly small rise of 0.2 percent in July from the previous year as new index components, including flat-screen televisions, pushed it down and forced past readings to be downgraded, the government said Friday.

At the same time, the core nationwide CPI, excluding perishables, rose for a second consecutive month, bolstering distant views that the economy is emerging from deflation, albeit weakly.

But another change -- the replacement of the base year for the CPI index -- forced past readings to be revised downward, casting doubt on the government's preparations to declare deflation finally dead.