Iran's telecommunication network enjoys the highest growth rate in the Middle East. One of the indicators that clearly illustrates this growth rate is the increase in the number of installed main lines. In 1978 there were only about 850,000 fixed lines installed in Iran. This number rose to about 1,767,000 by 1986 and to about 2,380,000 by 1989.
One of the objectives of the first five-year development plan (1989-1994) for the telecommunication sector was to add one million new fixed lines to the network. However, due to the establishment and expansion of many low-capacity and high-capacity exchanges, the actual growth rate that was achieved was considerably higher. In fact more than 3.1 million new main lines were installed during the period of the first five-year plan. Four million new lines were expected to be added by the end of the second five-year plan (1994-1999), which would increase the number of installed main lines to about 9,510,000 fixed lines. Table 3.1 shows the number of installed main lines in Iran for different years.
By March 1999 (end of the Iranian year 1377), there were about 8,285,000 main fixed lines in Iran. Even though this shows an almost 11% growth relative to the 1998 figure, about 1,225,000 additional lines should be installed by March 2000 in order to meet the objectives of the second five-year plan.
Along with the expansion of the size of Iran's telecom network, utilizing advanced methods in traffic measurement, maintenance and operational activities has resulted in considerable efficiency and network reliability enhancements in recent years. According to the annual report of the Telecommunication Company of Iran (TCI), network reliability increased to about 98% in 1997.