Last year there were 12,000 employees working in the phone and broadband services sector, the highest in 16 years.

The telecommunication sector is booming, with jobs steadily increasing year on year.

Last year there were 12,000 employees working in the phone and broadband services sector, the highest in 16 years. In the early 2000s, there were fewer than 7000 employees.

Many of the workers are immigrants.

Careers NZ estimates "line mechanics" in the telecommunications industry with between one and five years' experience can expect to earn between $32,000 and $60,000 – the lowest pay band among the jobs it lists in the ICT sector.

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IT helpdesk staff can usually expect to earn between $45,000 and $60,000 a year.

In December, the Ministry of Business, Innovation and Employment launched an investigation into the employment practices of some Chorus contractors and subcontractors.

The investigations followed years of angst between the union E tū, Chorus and its contractors over the pay and employment conditions of linesmen building the ultrafast broadband network and maintaining Chorus' copper network.

When the investigation was launched, Chorus spokesman Nathan Beaumont said it had been "very clear" that the use of volunteers was unacceptable.

Learn more about the information shown above, and explore more charts, at Figure.NZ's site.