MILWAUKEE (WTAQ) - The manufacturing economy of southeast Wisconsin kept expanding in April.

That’s according to a monthly survey by Marquette University and Milwaukee’s Institute for Supply Management.

A seasonally-adjusted index rose from 51.8 in March to 52.9 right now. Anything over 50 indicates growth.

The survey pointed out that some factories are working 24-7 to keep up with orders – and they’ve got more equipment on order. But the report also said some production spikes were due to economic uncertainty down the road.

The survey’s blue-collar hiring index fell from 57.3 last month to 51.6 this month.