Net orders for Class 8 trucks fell to just over 22,400 units in April, the lowest amount since November 2013, according to ACT Research.

Yet the numbers were close to an average monthly reading for an expanding economy, according to ACT. Much of the lull in orders was once again attributed to a hyperactive market at the end of 2014 and the beginning of this year.

“The current context is that the prior six months’ net orders run-rate was 400,000 on an annualized basis and some correction from these unsustainable levels was inevitable,” said Jim Meil, principal, industry analysis at ACT.

The medium-duty market was also down, posting 17,700 net orders of Class 5-7 vehicles in April. The number broke a fourth-month consecutive streak of year-over-year increases that began in December.

However, Meil noted that April 2014 was the second-strongest orders month in 2014 for medium-duty. He said that the streak ending “probably says more about the strength of the base period than about current weakness.”