Philadelphia's overtime expenses increased for the fourth year in a row.

The city spent $159 million in overtime in fiscal year 2015, which ended June 30, according to the city's fourth quarter report. The total spent was $37.6 million over what had been budgeted.

Overtime as a percentage of wage and salaries has increased each year since 2011, hitting 10.6 percent this past year.

"Overtime is always a challenge and we understand that," city spokesman Mark McDonald said Friday. "It is what it is. We're not pleased with it."

In 2011, when the city was recovering from the Great Recession, overtime dropped to $117.5 million, or 8.6 percent of payroll. It's increased every year since then. In 2014, the city spent $153.7 million in overtime, equaling 10.3 percent of wages and salaries.

The biggest users of overtime use in 2015 were the fire, police and streets departments, according to an analysis done by the Pennsylvania Intergovernmental Cooperation Authority, the city's fiscal watchdog.

The Fire Department went over its overtime budget by $10.3 million, spending a total of $36 million in overtime in 2015. Its initial budget for salaries and overtime was $261.2 million.

Similarly, the Police Department went over its overtime budget by $8 million for a total of $53 million used in overtime. The department had a budget of $621.3 million for salaries and overtime.

For the police and fire departments, McDonald said that it takes time to recruit and train new classes that will fill in vacant spots. Therefore, officers and firefighters sometimes have to cover for the people who left the department but whose positions were budgeted and needed.

"City departments each year need to balance staffing levels with reality of getting the job done," McDonald said. "Overtime is a tool that helps get the job done... you don't want to overly rely on it."

The Streets Department, which was budgeted for $75.2 million in salaries and overtime combined for 1,789 positions, ended the year with 1,664 employees and $95.5 million spent. The department went over its overtime budget by $7.4 million.

McDonald said the Streets Department went over its budget because many of the compact trucks used for trash pick-up were out of service. That required that a smaller number of crews go out for longer periods of time, sometimes an extra full day, to keep up with trash pick-up. Even then, only 65 percent of trash was picked up on time in 2015.

The city is planning to spend $7 million to purchase new compact trucks.

"We'll be replenishing the fleet and hope that will get us back on track," McDonald said.

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