NEW YORK CITY—Private equity real estate may be a global endeavor, but the most consistent performers among fund managers in the sector are based in the US. So says Preqin, headquartered here and in London, which ranked fund managers that have most consistently outperformed their peers, listing 21 US firms among the 26 worldwide that made the cut.

Although by virtue of its scale the Blackstone Group led with the largest number of funds in the first quartile—six of its funds made the top ranking—the most consistent performer among fund managers this year was JBG Cos. of Chevy Chase, MD. Three others achieved a perfect score of 1.00: San Francisco-based Carmel Partners, Belmont, CA-based Embarcadero Capital Partners and Atlanta-based Centennial Holdings.

The ranking of fund managers is based on a quartile ranking for each of their closed-ends, based on the funds' performance of the same geographic focus and vintage year. Funds with vintages of 2012 or newer are not considered, on grounds that they're too new to have generated a meaningful IRR. Nor are managers that have not been active since 2008, and Preqin has ranked only the managers that have raised at least three funds.