Why does approximately 1/10th of the NYPD make less than 1,000$ a year?

I requested from the NYPD the below,

The number of New York City Police Department employees who were paid between 0 and 1000 dollars in 2015.

As an example, records show the following employees and payroll
	Supall, Tiffany D	3$
	Johnsen, Denise L 	3$ 
	Dejesus, Altagracia	3$
Or simply confirm that it is possible for a large number of employees to be paid less than 100$.

The average dollar cost in benefits per New York City Police Department employee.

List of benefits such as health care, dental, parking, transit that a
	* School Crossing Guard 
	* Police Communications Technician
	* Motor Vehicle Operator
receives.

The minimum number of hours or pay an employee must work to receive benefits. 

The number of New York City Police Department employees who worked less than 100 hours in 2015.

I received this

Which stated that:

Responsive to point one in your request, the number of NYPD employees who were paid between 0 and 1,000 dollars in 2015 is 3,101.

What are the situations that could have someone get less than 1000$ a year?

Getting fired/quiting X days into the start of the year?
Starting at the NYPD with only X days left in 2015.
Why are so many people paid 7$? http://seethroughny.net/payrolls/