HC Deb 15 November 1937 vol 329 c21
37. Mrs. Tate

asked the Postmaster-General whether the provision of night operators for telephone exchanges in country towns and villages is based on the size of the population or on the average number of nightly calls over a given period?

Major Tryon

The provision for night operating in telephone exchanges is based on the volume of traffic revealed by representative records covering a given period.