A recent nationwide survey of car repair bills has found the average cost to fix regular cars has gone up for the first time in six years, while hybrid car repair costs actually decreased.

According to CarMD, which has been collecting auto repair data since 1996, but only started releasing its findings for the past three years, non-hybrids increased by about 11.6 percent in the Northeast, and 10 percent in the rest of the country.

This result was released based on analysis made for the time period of Jan. 1, 2012 through Dec. 31, 2012 and it surveyed repairs made by 161,000 ASE-certified technicians.

After all that data crunching, researchers from CarMD found hybrids experienced a decrease in average cost of repairs and – formally the inauspicious record holder of the single-most expensive type of auto repair – hybrids happily dropped from that top spot.

“The most expensive repair in 2011 was ‘replace hybrid inverter assembly’ at $4,098, which decreased by nearly 5 percent in 2012,” wrote CarMD’s researchers. “Hybrid repairs no longer hold the top spot, which is now ‘Replace Transmission Assembly and Reprogram Electronic Control Module’ at more than $5,400.”

It is believed a prime reason hybrids’ stats improved is there are simply many more hybrids on the road. According to the HybridCars.com Dashboard, 2011 saw 268,807 hybrids sold in the U.S., 2010 saw 274,763 hybrids sold, 2009 saw 290,272, and 2008 – a year of alarming gas price spikes – saw 314,271 U.S. hybrids sold.

So the rate has been over a quarter million hybrid sales per year for the past several years.

Another reason hybrid repair costs are believed to have dropped is the number of technicians qualified to repair them has increased, as has the number of suppliers of hybrid-specific parts.

As for regular vehicles, contributors to cost increases include the fact more people are hanging on to their vehicles longer. The average age is now over 11 years, and this leads to a higher incidence of “catastrophic” or major repairs which spiked 24 percent in 2012. Also a culprit for higher repair costs mentioned was record heat in regions in 2012.

The researchers also found more vehicle owners are making minor repairs themselves, keeping their cars out of the shop. And, newer cars are making fewer trips to the shop, indicating an increase in reliability.