Because the CPI is an indicator of the cost of living governments use CPI data to set payments for large groups of people. In the US there are more than 2 million workers whose wages are covered under collective bargaining agreements. When the CPI rises their wages rise as well, giving them increased spending power. In addition, nearly 50 million Social Security recipients have their benefits tied to the CPI. Other groups who will receive an increase in benefits when the CPI rises includes retired military and government workers and food stamp recipients. In truth, every single American tax payer is impacted by the CPI since the US tax code is adjusted based on CPI readings.