The Cost of Living Adjustment, if due, is effective every August 1st. But there are no more "August firsts" in the current Contract, therefore, no more COLAs.
Gas and most things are included in the Consumer Price Index. (But tax increases aren't!!! That would make the Government look bad.)
It takes about a 3.5% increase in the CPI from May to May to trigger a COLA payment.
Usually, when a new Contract is agreed to, there is no COLA provision for the first August 1st. The formula would likely start August 1, 2014 and thereafter.