• Job cuts: 20,000

Cheap gas has come with a very painful cost for many people who work in the energy industry.

The tumble in oil prices from $100 a barrel last summer to as low as $43 in March has forced many companies to lay off workers.

Schlumberger (SLB), which provides tools and services used for drilling for oil and natural gas, announced 11,000 job cuts in April. That's in addition to the 9,000 positions it said it would cut in January.

Oil service companies like Schlumberger have been slammed by the steep decline in drilling activity. The number of rigs searching for oil has tumbled nearly 60% since October to four-and-a-half year lows.

Related: Gas prices set to fall

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