The Gini coefficient, Palma ratio, and the ratio of the percentage of tornadoes occurring on days with 20+ tornadoes to the percentage of tornadoes occurring on days with 1–9 tornadoes were used to measure the concentration of tornadoes in the USA for each year over the period 1954–2017. The Gini coefficient and Palma ratio were also used to measure the concentration of tornado power. All three metrics illustrate that most tornadoes are concentrated on relatively few days and that power is even more concentrated. Trend tests illustrate that tornadoes are becoming more concentrated over time, but the power dissipated by tornadoes is becoming less concentrated. Despite the declining trend, most of the power dissipated by tornadoes remains highly concentrated on relatively few days.

使用基尼系数，帕尔马比率以及在发生20+次龙卷风的日子中发生的龙卷风的百分比与在发生1–9次龙卷风的日子中发生的龙卷风的百分比之比，来测量美国每年在过去一年中龙卷风的浓度。 1954年至2017年。基尼系数和帕尔马比率也用于测量龙卷风能量的浓度。所有这三个指标都表明，大多数龙卷风都集中在相对短的几天内，而力量则更加集中。趋势测试表明，随着时间的流逝，龙卷风变得越来越集中，但是龙卷风消散的力量却越来越少。尽管趋势呈下降趋势，但龙卷风消散的大部分力量仍集中在相对几天内。