The economic optimism index in the US rose in October to 57.8 points from 55.7 points a month earlier, data from the Investor’s Business Daily and TechnoMetrica Institute of Policy and Politics showed. The growth of the index, which is noted for the second month in a row, came as a surprise to experts who had expected it to drop to 54.6 points. The index exceeds the mark of 50 points for the past 25 months. This is the longest period in the entire history of the study. In October, two of the three components of the index showed growth - an indicator of personal prospects for the next six months and an indicator that determines confidence in the federal economic policy.