 At that time, the weights for indices like CPI-U and CPI-W were updated only once per decade; today, they are updated in January of even-numbered years.However, even with this more frequent updates, the CPI-U and CPI-W might still be excessively slow in responding to new technologies.For example, by 1996 there were over 47 million cellular phone users in the United States, but the weights for the CPI did not account for this new product until 1998.