New Delhi, July 25 -- Motorists using national highways with bridges, tunnels, flyovers and elevated stretches are set to pay less tolls under a new formula, with the National Highways Authority of India (NHAI) on Friday directing all its field offices to begin processing toll notifications and revisions under the amended rules. The move follows the Ministry of Road Transport and Highways' July 1 amendment to the National Highways Fee (Determination of Rates and Collection) Rules, 2008, which changes how user fees are calculated for highway stretches involving one or more independent bridges, tunnels, flyovers or elevated highways. Under the revised rule, toll will be calculated by adding 10 times the length of such structures to the length of the remaining highway section, or five times the total length of the highway section, whichever is lower. Structures measuring 60 metres or less will not be treated separately for this purpose....