BALTIMORE – A published list of top salaries for the Baltimore City school district in 2013-14 is a little confusing at first.

One column of the spreadsheet lists “regular earnings,” which is obviously what each employee was paid in regular salary or hourly wage.

MORE NEWS: VIDEO: Throng of illegals waits to be rafted across Rio Grande

But there are two more columns – titled “additional earnings” and “total earnings,” that trip the alarms.

The “additional earnings” column had some pretty big numbers, and made many of the dollar figures under “total earnings” much larger.

What “additional earnings” are they talking about? How could it involve so much money?

A March 2015 article from the Baltimore Sun clears up the mystery, and not in a pretty way.

It seems that the very expensive “extra earnings” paid out by the Baltimore City district represented “bonuses, overtime pay and accrued leave,” according to the newspaper.

In other words, a whole lot of unnecessary perks ended up pushing a lot of employee salaries much higher than they would have been, and costing the taxpayers a handsome sum.

In 2013-14, a total of 659 Baltimore City school employees made at least $100,000 in regular and additional earnings combined – and that’s not counting the untold cost of insurance and other benefits.

MORE NEWS: VIDEO: Ron Paul appears to suffer ‘stroke’ during livestream

Those 659 employees were paid a combined $68 million in regular earnings, plus another $5.8 million in additional earnings, totaling $75 million.

All but eighteen on the list of 659 in the “six-figure club” received “additional earnings” – including 125 who were paid at least $10,000 for unused leave, various types of bonuses and overtime pay.

Four employees made at least $100,000 in extras. One of them – interim district CEO Tisha Edwards – was paid $121,830 in straight salary and a whopping $217,156 in additional earnings, totaling $338,986.

Most of the extra money was compensation for leave time she did not use in her 10 years with the district, the Sun reported. While most of that time was spent in lesser positions at lower pay, district policies allowed Edwards to cash out her unused leave time at the rate she was making as CEO.

Another good example was school district police officer Leonard Winfield, who made $52,228 straight salary and $125,851 in additional earnings, bringing his salary to $193,607.

The picture gets worse when the entire payroll is examined. According to the Baltimore Sun, the school district paid more than $600 million in salary to approximately 13,000 employees that year, including $46 million in “additional earnings.”

While all of this was happening, the district was running up a $72 million budget deficit that threatened to force layoffs in the district for the first time in more than 10 years, according to the Sun.

Some of the blame obviously goes to school district employee unions, which negotiate expensive perks for their members. But many 659 highest earners, including most near the top of the list, were administrators who are not represented by unions.

Only four teachers made the top 100 on the list. The vast majority of those had the title of “principal” or “executive director.”

School board President Shanaysha Sauls said the amount of money paid out for perks is “not something we should feel comfortable with,” according to the Sun.

“We have moved aggressively and in good faith to show that we want to do right by our people in terms of compensation,” Sauls said. “But we need to have an honest conversation about being respectful to people, while not being disrespectful to the organization.”

How about a little respect for the taxpayers, who have been forced to fund this irresponsible payroll for who knows how many years?

After all, according to the federal Department of Education, only 14% of Baltimore City students are proficient in critical subjects like reading and math.

Alissa Mack contributed to this report.