U.S. automotive recalls fell in the second quarter to 5% under the five-year average, a new report says.

Recalls decreased 4.5% quarter-over-quarter to 234 events, according to Sedgwick, a claims and productivity management solutions provider. The five-year average is 247.

But the number of effected vehicles rose in the quarter by 8% to 8.2 million, marking the third quarter in a row of volume increases, Sedgwick says. The number was 7.5 million in the fourth quarter.

Electrical systems were the top cause of recalls – 51 events, or about 22% – for the second quarter in a row, the first time in a decade that any cause other than equipment was the single most dominant cause of recalls in two consecutive quarters.

Sedgwick says “back-over prevention,” or safety measures and technology intended to prevent accidents involving a vehicle backing over a thing or person, was behind the most recalled units, or 1.7 million across six recalls. Air bags came in second, with 1.32 million units affected across five recalls.

The volume of recalls at the halfway point of the year, at 479 events, is consistent with the five-year average of 484, Sedgwick says.

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