Ministries and agencies “arbitrarily interpreted” guidelines for employing disabled people and counted people who were retired or even dead among their numbers in an attempt to meet legal quotas, an investigative panel said Monday.

The committee of lawyers and other experts tasked with looking into the data falsification concluded that such “sloppy handling” had occurred for decades in some cases.

The government has said the percentage of people with disabilities in national office workforces as of June last year was actually 1.17 percent, instead of the 2.50 percent figure previously announced. Japanese law requires public institutions to meet the 2.5 percent quota, while the quota for the private sector is set at 2.2 percent.

After recognizing 3,700 people had been inappropriately included in the total workforce reported for 28 of the 33 national administrative entities it surveyed, the investigative panel said in its report that the situation was “extremely serious.”

The misconduct is regarded as having overshadowed Japan’s aim to achieve a more inclusive society.

Separately, the labor ministry announced that local municipalities last year inflated the number of disabled people reported as employed by more than 3,800.

The government bodies failed to check disability certificates or other information for 3,426 of them, and also counted 91 people who had retired — including three who are dead — according to the report.

“There is no excuse,” said Gan Matsui, a former superintending prosecutor at the Fukuoka High Public Prosecutor’s Office who headed the panel, at a press conference.

The panel found the National Tax Agency’s overstatement was most serious, inappropriately counting 1,103 people, followed by the Land, Infrastructure, Transport and Tourism Ministry with 629 miscounted including 74 people who had already retired.

The Internal Affairs and Communications Ministry and the Environment Ministry counted staff with limited eyesight based on their uncorrected vision, rather than corrected vision, according to the report.

Most entities were unable to indicate when the falsification began, although the Finance Ministry said it started around 1960 or later.

The panel said the Health, Labor and Welfare Ministry, which is in charge of promoting employment of the disabled, neglected to fully grasp the situation for many years.

“We will give serious attention to the probe results,” said Chief Cabinet Secretary Yoshihide Suga, adding that the government will work to prevent such malpractice and achieve the legal quotas properly.

While all surveyed entities denied intentionally misreporting employment data, the panel said it can assume they had intended to overstate the numbers “to meet the legal rates.”

The labor ministry requires government agencies and private companies to report employment rates of the disabled as of June 1 every year.

“The Health, Labor and Welfare Ministry and every administrative entity has been given harsh reviews,” labor minister Takumi Nemoto said. “We will give serious thought to this situation.”

On Monday, the government said it plans to employ by the end of fiscal 2019 a total of 4,073 people with disabilities at public institutions that have failed to meet their quotas.

It also announced preventive measures, including keeping a list of disabled employees at each public institution and copies of their disability certificates and other necessary documents.

A law promoting the employment of people with disabilities requires central and local governments and private companies to hire, in principle, people with physical or mental disability certificates, as well as those with intellectual disabilities.

If a company with more than 100 employees fails to meet the target, a fine of up to ¥50,000 per employee shortfall per month is charged and in some cases its name is disclosed, while such a rule is not applied to government bodies.

In June the labor ministry began investigating ministries and agencies over allegations of misreporting dating back to 1976, after receiving several inquiries about how to calculate the employment rates of disabled people.

The government announced in August that its investigation had confirmed 27 national administrative entities inflated reported numbers of disabled employees by a total of about 3,460.

The number was revised upward with the latest probe, as the initial figure had counted two part-time workers as one person.