With the great increases in business establishments and new residences being built, it was a tremendous task to figure out what lines had to be installed where, how many customers would be coming into a specific area, and even how many new telephone numbers would be needed.
How many new phone lines were installed in the 1960's and 1970's? Here's an excerpt from the article below:
The 1960 to 1970 Phone Demand
On January l, 1976, there were approximately 26,000 telephones in St. Tammany Parish. There were eight telephone exchanges serving St. Tammany Parish in 1976, with different prefixes for Covington, Folsom, Bush-Sun, Mandeville, Madisonville, Lacombe, Slidell and Pearl River.
Slidell at that time had two prefixes, having added "641" a few years earlier.
When the NASA complex moved near Slidell, demand for new telephones shot up 63.8 per cent in Slidell. Between 1966 and 1976 telephone "demand" in St. Tammany Parish was up 37 per cent from the decade before. Between 1961 and 1971, the number of phones in St. Tammany almost doubled.
This is quite a change from when telephone service began in St. Tammany.
In the Early Years of Phone Service
In 1926 there were 917 phones in the parish. In 1931, there were 1,136, and due to the Depression, there were only 1003 phones in 1936. Then, in 1941, the number of phones in the parish climbed to 1377, and later,from 1946 to 1951, the number of phones increased a substantial 121.8 per cent, reaching a total of 4225 in January of 1951.
A 64.6 per cent increase took place between 1951 and 1956, making a total of 6953 phones in the parish, and another 28.5 per cent increase came between 1956 and 1961, ending up with 8932 phones in St. Tammany.
In 1966, there were 14,643 phones in the parish, and,in 1971, there were 18,839 phones in the parish.
When individual phones increase, the pressure rises to add another exhange. Since one "exchange" only offered ten thousand numbers, then more exchanges would also need to be established.
When I moved to Covington, the 892 exchange meant you lived somewhere around Covington, and the 626 exchange meant you lived around Mandeville. Madisonville was 845, Bush was 886 and Slidell was 643. Over the years, more exchanges were added to keep up with the demand for new telephone numbers.
Here is an article from 1976 telling about the challenges of forecasting new phones for St. Tammany Parish. Click on the image to make it larger.
Then along came the 1990's and cell phones. It took a while but gradually people began disconnecting their home landline phones and just communicated through their cellphones. That kind of disrupted all the forecast models about landline phone cable installations.