The Green Street Commercial Property Price Index rose 1.0% in July, the firm said. Over the trailing twelve months, the all-property index has increased 5.2%.

Rental income is 2-3% higher over that period, the firm said. The remainder of the appreciation stems from lower cap rates.

Green Street builds its monthly index on valuations of REIT-owned assets. The firm says the approach reflects where the commercial real estate market currently stands, ahead of traditional transaction data.

In June the index was unchanged. Over the twelve months ended that month, the all-property index had increased 4.1%.

"Price gains have been modest because cap rates continue to be quite sticky," said Peter Rothemund, Co-Head of Strategic Research at Green Street, in the July report. "And it's unlikely that they will compress in the near term given current interest-rate expectations."

The index increased 1.6% in May. Over the twelve months ended in May, the all-property index had increased 4.1%. "Property prices have been creeping higher due to NOI growth and, in a few sectors, lower cap rates," Rothemund said in the June report.

In April the index decreased 0.1%. Values of life science properties declined, the firm said. Pricing in other sectors was unchanged. Over the twelve months ended in April, the all-property index had increased 3.1%.

"Buyers have been disciplined," Rothemund said in the May report. The index increased 0.4% in March. Over the twelve months ended that month, the all-property index had increased 2.6%.

Green Street says the index is value-weighted, measuring aggregate price movements rather than providing an equally weighted view. The firm also launched a Canadian index in June, which showed a 0.2% increase over the prior quarter and a 0.9% decline over the trailing twelve months.

Green Street has published the index for 27 years. The firm tracks 12 core sectors across more than 25 countries. The index models values on fundamentals including cap rates and net income, the firm said.