Social Security COLA less than 2 percent GREAT BARRINGTON, Mass., Oct. 9 (UPI) -- A think-tank in Massachusetts said Social Security benefits will rise between 1.5 percent and 1.7 percent in 2013. The Labor Department is scheduled to release figures on September's inflation rate in mid-October and that is the last of 12 monthly inflation estimates that are used to calculate the cost of living adjustment for Social Security recipients, CNNMoney reported Tuesday. The increase will be about half of the 3.6 percent increase of 2012, said the American Institute for Economic Research The cost of living calculation, however, is based on purchases that are not particularly typical of the elderly, who are the recipients of Social Security. The price of motor-grade gasoline rose 2 percent, while medical care costs have jumped 4.1 percent. The costs of every day household goods also rose 2 percent over the past 12 months, the think-tank estimated. With purchases made by seniors leaning more towards items that have faster price inflation, the increase in benefits is leaving seniors slightly behind, AIER said. They're falling behind by about a half a percentage point a year or so. It's not a huge amount, but over time that adds up," said AIER director of research and education Steven Cunningham.