Almost one-fifth of the buses from the Capital Area Transit System are unusable because they are too old and dilapidated to safely drive on the road.

In the most recent quarter, CATS averaged six breakdowns a day. CATS CEO Bob Mirabito acknowledged that this is the No. 1 reason why CATS isn’t delivering more reliable services.

Recently, Mirabito released data detailing the quality of each of his individual buses to drive his point home.

In total CATS has 104 vehicles, including buses, trolleys and vans. Of those, 19 are parked and not able to drive because they are either past their useful lifespan or irreparably damaged.

CATS buses typically are supposed to last 12 years, or 500,000 miles, Mirabito said, “whichever comes first.”

But several CATS buses currently in use are as much as 18 years old and are approaching 900,000 miles on the odometer.

There are 17 buses still on the road that have more than 500,000 miles on them.

While voters approved a tax in 2012 to expand CATS routes and improve overall service, the additional tax money falls short of what would be needed to purchase enough buses to fix the fleet.

Mirabito says there are a total of $25 million worth of needs for the fleet over the next four or five years.

The agency is considering financing options to purchase 12 buses a year.

CATS has this year received 11 additional buses. Six of those are used, and already have between 360,000 and 435,000 miles on them. The other five were purchased new and cost a total of $2.2 million. Brand new buses cost about $440,000 each.

CATS already has a purchase order for four new buses to be delivered next year, but Mirabito said he hopes to increase the request to 10 or 12 buses.

Together Baton Rouge, a faith-based nonprofit that helped pass the CATS tax, graded the bus system last week on its delivery of improved services, giving them both positive and negative marks.

CATS got an A for reducing overall trip times. The new routes have successfully reduced the time it takes to get from one point to another once a person steps onto a bus.

But according to Together Baton Rouge’s own volunteers who monitored routes, they said CATS was more than five minutes late to a scheduled route almost 40 percent of the time. CATS’ standard measurement for whether a bus is on time is whether it arrives within 10 minutes of the schedule.

Follow Rebekah Allen on Twitter @rebekahallen. For more coverage of city-parish government, follow City Hall Buzz blog at http://blogs.theadvocate.com/cityhallbuzz/.