The occupancy mix has also changed.
The biggest take-up in space, as the chart below shows, has come from the so-called pureplay online retailers, firms which don’t have physical stores and only sell online, such as Boohoo.
The warehouse will be Royal Mail’s biggest parcel hub, processing more than a million packages a day.
When this vast logistics park is eventually filled, some 15,000 people are expected to be employed here.
“There’s also increased demand in manufacturing and automotive.