In times of uncertainty, building construction can be a good barometer for the economy.

Industry analyst Dodge Construction Network, Boston, reports construction activity showed strong signs of growth in June. According to Dodge data released in late July, construction starts increased by 16% in June, reaching a seasonally adjusted annual rate of $1.33 trillion.

Starts refer to the number of building projects launched or started. Dodge measures them in terms of their dollar value, and the seasonally adjusted annual rate refers to the total value of starts that would take place over the course of the next 12 months if activity continues at the current pace.

Starts are a composite of figures for different subsets of the building industry. In June, some subsets showed strong growth, while others were in the negative.

Of all the contributors, nonresidential starts drove the trend. According to Dodge, they increased by a whopping 39% from an annual rate of $456 billion in May to $635 billion in June.

The two primary drivers of growth in this sector were commercial and manufacturing buildings. Commercial starts were 78% higher in June, fueled by new data centers, while manufacturing starts increased by a whopping 304%, climbing on the basis of a few very large projects, according to Dodge.

On the other end of the spectrum, residential building starts declined 1% in June to a seasonally adjusted annual rate of $366 billion. Single-family starts decreased by 2%, and multifamily starts remained flat.

The increase in commercial starts was more than enough to offset decline in single-family starts.

According to Sarah Martin, associate director of forecasting at Dodge Construction Network, “risks remain elevated that construction starts will be more subdued in the back half of the year.” She cites “ongoing uncertainty over trade policy and the broader economy” as factors that may hold back growth.