The US service sector grew for the eighth straight month in August in-line with employment figures, according to a trade group survey.

The pace of growth slowed though, fueling speculation that the US economy may be running out of steam.

The service sector accounts for around 80% of employment in the US, making it a significant barometer of economic health.

The Institute for Supply Management’s service-sector index was at 51.5 for August, lower than the 53.5 expected by economist and the 54.3 figure for July.

The index measures growth with readings above 50 signaling expansion while figures under 50 show a decline. In November of 2008 the index fell to 37.2.

There are fears that US economic growth for the year may have reached its zenith, as the August reading was the lowest since January.