Dec. 18, 2012 | The chained CPI is a cut in Social Security Benefits and a "stealth" tax hike. As Republicans in Congress take a hard line in the sand against higher tax rates for millionaires and billionaires, they are demanding a Social Security benefit cut through a lower Cost of Living Adjustment (COLAs). The lower COLA would result from the adoption of a new formula for calculating COLAs called "Chained CPI." What is that and what will it mean for working people, especially middle-and lower-income families? Learn about it here. View explanatory graphic here.