Jobs in the Texas oil patch dropped for the first time in almost two years, according to the state’s workforce commission.

The number of workers handling exploration and drilling duties fell by 500 to 247,700 in November compared with the previous month, according to the latest data from the Texas Workforce Commission. Snapping a streak of 23 months for oilfield expansion, the state is weathering volatile oil prices that have lost more than a third of their value since October.

“We have seen tremendous growth in the oil and natural gas industry in Texas, including consistent job expansion, but growth is not guaranteed,” Todd Staples, president of the state oil and gas association, said Friday in a statement.

Home to a pair of the world’s busiest shale oil fields -- the Permian Basin and the Eagle Ford -- the Lone Star State has yet to fully climb back to the high of 308,900 upstream workers reached at the end of 2014, before a decline in crude prices that lasted more than a year. The state’s data only covers so-called upstream jobs related to oil and natural gas extraction, excluding other large sectors such as pipelines and refiners. It’s subject to historical revisions later on, according to the Texas Oil & Gas Association.