Amid a growing economy and greater consumer spending power, retailers are rapidly expanding their logistics networks, and that expansion continues to strengthen the industrial sector, according to Marcus & Millichap’s Midyear 2018 Industrial Outlook report.

E-commerce sales rose 15.2 percent in the second quarter from a year earlier, accounting for 9.6 percent of total retail sales. Rising Internet sales are driving delivery costs higher as freight haulers approach their capacity, as well. In addition, industrial deal flow grew at a greater rate than other property types on a year-over-year basis in the second quarter, while also bringing sales volume in the same quarter to a new high of $18.2 billion.

U.S. firms spent a record $1.5 trillion on shipping expenses in 2017, as increased demand has also pushed transportation costs higher. Companies are strategically combating the increased cost of delivering products by taking up more space in dense resident