A measure of future U.S. economic growth rose slightly in the latest week, while the annualized growth rate fell, a research group said on Friday.

The Economic Cycle Research Institute, a New York-based  independent forecasting group, said its Weekly Leading Index  rose to 121.9 in the week ended June 8 from 121.3 the previous week. That was originally reported as 121.6.

The index's annualized growth rate fell to -3.0 percent, its lowest since late February of this year, from -2.2 percent a week earlier. That was originally reported as -2.0 percent.