This ETF has its highest concentration in the Brazilian oil company Petrobras ( PBR), which may explain why it is lagging.

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In certain industries, such as oil and gas, concentration is especially acute, with only two or three auditors ruling the market.

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Before we started torching carbon stored in forests and then carbon stored underground as coal and oil, the carbon dioxide concentration of our atmosphere was about 280 parts per million (ppm).

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Because of this continuing concentration of supply, the risk of a disruption to oil flows will continue to be a threat, and may even rise.

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The problem with oil is not its scarcity, rather its concentration.

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"Rising imports of oil and gas into OECD regions and developing Asia, together with the growing concentration of production in a small number of countries, would increase our susceptibility to supply disruptions and sharp price hikes, " Tanaka said.

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