Regular attendance has fallen across all regions, ethnicities, deciles, and year levels since 2015, prompting the National Party' education spokesman Paul Goldsmith to call it a "truancy crisis".
Today's data will also show that about half of the decreased attendance from 2015 to 2019 was due to illness, a quarter was due to truancy, and a quarter was due to families taking holidays during term time.
The biggest truancy increases were from younger students, rather than senior students wagging class.
Associate Education Minister Jan Tinetti has previously said there are many reasons for truancy, and the Government was focused on lifting student engagement via refreshing the curriculum, providing lunches and period products in schools, and removing school donations.
Truancy services are also being reviewed.
On Monday the Herald reported on a Ministry of Education briefing note from December 2020 showing how under-resourced truancy services are.
Attendance Services, which works with students aged 6 to 16, receives $9.676 million annually and reaches around 12,000 frequently-absent students, and another 10,000 students who are not enrolled in any school.
But some 30,000 students who are chronically absent - missing at least three days of school a fortnight - were out of reach, the briefing note said.
"These funding settings will place limitations on progressing this work as schools will need to try and work differently within the same level of funding."
The briefing note said that ensuring students regularly go to school was a collective responsibility involving students, whānau, schools, attendance services and wraparound support.
Attendance was poorer in lower decile schools and among Māori and Pasifika students, and attendance at the primary and intermediate level - Years 1 to 8 - had fallen by 14 percentage points since 2015. Half of that drop had happened in 2019 alone.
While attendance increased in term two in 2020, following the national lockdown for the Covid-19 response, compared to 2019, the August lockdown in Auckland had appeared to take a harder toll.
"For Auckland students, it has taken longer to get back to 2019 levels after the August lockdown - and Covid-19 appears to be worsening existing inequities in school attendance," the briefing note said.
"For some, the experience of Covid-19 has triggered poorer post-lockdown attendance and engagement."
A police truancy overview from July last year showed a single truancy officer for the 80 schools in the Waitematā East area, despite truancy being on the rise.
The overview said that local schools wanted to hire their own truancy officers instead of the current model of contracted services via the ministry.
