When comparing economic performance across time periods, a black swan event like a financial crisis or an unexpected global disruption can lead to sharp declines in GDP. These events, being outside the control of policymakers, can distort the true picture of economic performance. For instance, one period may see a severe downturn, while the subsequent period benefits from an organic recovery, making it seem as though one era underperformed while the other succeeded, purely due to timing.
I've read about different techniques such as time decomposition, counterfactual analysis, structural break analysis, dummy variables, rolling or moving averages, natural experiment design, trend-cycle decomposition. However I'm not sure which of these are the most appropriate for the given question.
Allan Lichtman prides himself on his "The Keys to the White House" method of predicting the next president of the U.S., which he claims he has done correctly since 1984 (although he got 2000 wrong, which he still actively disputes).
His sixth key "Strong Long Term Economy" described as "Real per capita economic growth during the term equals or exceeds mean growth during the previous two terms.". Lichtman has stated that this key will go in favor of Presidential Candidate Kamala Harris, stating that her administration's period from 2021-2024 has equalled or outperformed the averaged GDP growth of the two prior administrations from 2012-2020.
To me, turning this key in favor of the current administration does not seem remotely logical, especially when you look at the official figures for GDP growth. Just at the end of the previous administration, a sharp decline in GDP of ~5% was observed, due to the COVID-19 Black Swan Event. Then the current administration rode the wave of the organic bounce back in GDP as the country opened up again. To me it seems like Lichtman has ignored this fact in its entirety and has caused the averages to be affected negatively from 2012-2020 and positively affected in the current administration's term.
My question is, using the official GDP numbers of the U.S. combined with the appropriate mathematical techniques to adjust for COVID's impact, how does the average GDP growth/decline compare between the time periods 2012-2020 and 2020-2024?
