Energy stocks are in the middle of one of their best rallies in nearly 50 years

Oil pipelines, pumping rigs, and electrical transmission lines dot the landscape along California's "Petroleum Highway" (Highway 33) running along the northwestern side of the San Joaquin Valley on April 24, 2020, near McKittrick, California.
George Rose | Getty Images News | Getty Images

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Amid the recent rotation into value stocks, one sector stands out: energy.

According to data from Ned Davis Research, the sector just posted its best 21-day relative return since at least 1972, up more than 30% versus the S&P 500.

And with Thursday's move higher, the sector is up about 13% so far this month alone, making it far and away the best performing S&P group. By comparison, financials is the second-best performer, up just 3%.

Notably for the stocks on Thursday, oil prices reached their highest levels since March with Brent crude oil even breaking above $50 a barrel.

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