1月中下旬，中美兩國官方統計機構先後發佈2021年第四季度及全年國民經濟核算數據，引起各國經濟分析機構和國際機構的廣泛關注。比較有代表性的一種觀點認為，中國第四季度經濟增長明顯下降，而美國第四季度經濟增長明顯超出預期，因此，美國的增長態勢好於中國。本人認為有必要對上述觀點進行解析。

首先，直接將中美兩國經濟數據進行比較，似乎美國經濟增速明顯超過中國。據中國國家統計局發佈的數據，2021年第四季度中國GDP同比增長4.0%，而據美國商務部經濟分析局發佈的數據，當季美國GDP同比增長5.5%，增長率確實高於中國。但應該看到的是，2020-2021年期間，由於受疫情影響，兩國經濟增長率都出現了很大波動，季度經濟增長率都曾出現較大幅度下降，且兩國經濟恢復步調存在差異。為此，以2019年四季度為基期，觀察兩年平均增長率，似乎更能反映增長態勢。美國2020-2021年第四季度的季度平均增長率為1.6%，而中國為5.2%，比美國高出不少。其中的主要原因，是2020年第四季度美國經濟剛剛出現恢復。

其次，2021年第四季度中美兩國GDP環比增長率比較接近，且美國的增長受到補充庫存的較大影響。2021年三、四季度中國GDP環比增長率分別為0.7%和1.6%，美國分別為0.6%和1.7%。但兩國統計機構在數據表達方式上習慣不同，中國直接公布GDP的季度環比增長率，而美國公布的是季度環比增長率摺合年率的數據。此外，2021年第四季度美國能夠實現較高增長，很大程度上是受到補充庫存的影響。按照2012年不變價計算，2021年四季度美國GDP（摺合年率）環比增加3271億美元，其中庫存增加2403億美元，對GDP增長的貢獻率達到73.5%。2021年四季度庫存增加額占當季GDP比例略高於0.9%，而本世紀以來美國各季度庫存增加額佔GDP比例的平均值為0.2%。如果庫存比例與平均值持平，則2021年第四季度的GDP環比增長率僅為0.7%，摺合年率為2.9%，就會是一個比正常水平略高的增長率。

再者，2021年美國經濟實現了5.7%的高增長，是1985年以來的最高紀錄，但應該注意的是，這是在2020年出現經濟下降3.4%後的恢復性增長，兩年平均增長率只有1%，還低於美國的長期平均增長率。特別需要指出的是，美國為扭轉2020年下降勢頭並在2021年實現經濟增長，付出了巨大的代價。一是美國財政連續兩年出現大規模赤字，根據美國財政部及行政管理和預算局發佈的聯合報告，2020和2021兩個財年的赤字分別高達3.13萬億美元和2.77萬億美元，為美國歷史上赤字規模最大的兩個年份，赤字佔GDP的比例分別高達15.2%和12.4%。同時，美聯儲大量增發貨幣，2020、2021年兩年內美國廣義貨幣M2增加了6.3萬億，而2019年末美國M2餘額為15.4萬億美元，可見近兩年美國貨幣增加規模之大。由於財政大量超支和貨幣大量發行，造成美國在2021年出現嚴重通貨膨脹。根據美國勞工統計局的數據，2021年12月美國消費者價格指數（CPI）同比漲幅達到7.0%，這也是1982年以來美國月度CPI漲幅的最高紀錄。與之相對照，2021年中國消費者價格指數（CPI）僅上漲0.9%，形成了高增長、低通脹的組合。

最後，對2022年美國經濟形勢的估計不宜過於樂觀。日前，IMF發佈經濟預測報告，認為美國2022年經濟增長4%，中國經濟增長4.8%。在筆者看來，這樣的估計對美國可能過於樂觀，對中國的估計又可能過於悲觀。如上所述，美國2021年實現較高經濟增長，採取了刺激力度巨大的財政政策和極為寬鬆的貨幣政策。現在看，為了應對嚴重的通貨膨脹，2022年美國財政部將明顯收縮財政赤字規模，美聯儲也已經明確了加息和縮減資產負債表的政策方向。在美國宏觀經濟政策力度明顯減弱的情況下，加上2021年底以來新冠變異病毒奧密克戎在美國大範圍蔓延，抑制了消費需求且擾亂了供應鏈，美國經濟增長將受到明顯影響而放緩。美國知名經濟分析研究機構世界大型企業聯合會2022年1月份預測美國今年GDP增長3.5%，明顯低於IMF的預測。

對中國而言，由於抗擊疫情成效較好，經濟較早得到恢復，經濟增長率已從大幅度波動的狀態回歸到比較平穩的狀態，而且財政政策和貨幣政策都有較大的調整空間，2022年有望實現5%以上的經濟增速。

In mid- to late-January, authorities in China and the U.S. released their respective Q4 and whole-year GDP statistics, having drawn close scrutiny from domestic and international analysts and watchers. A widely held reading is that while the Chinese economy slowed significantly in Q4 2021, the U.S. economy markedly overshot expectations in the same period. Hence the conclusion that the U.S. economy is in a better shape than China's. But I beg to differ.

On the surface, it seems that the U.S. economic growth rate outpaced China. According to the Bureau of Statistics of China, the Chinese economy grew 4 percent year-on-year in Q4 2021. The data released by the U.S. Department of Commerce's Bureau of Economic Analysis suggests a GDP growth of 5.5 percent year-on-year in Q4 2021. The comparison seemingly shows that the U.S. economy is growing faster than China in Q4.But we should not disregard the fact that in 2020 and 2021, both economies saw major fluctuations in their aggregate economy and a substantial contraction in quarterly economic growth. Moreover, the two economies diverge in terms of phase of recovery.Therefore, it makes more sense to examine their growth using Q4 2019 as the baseline, with 2019 to 2021 as a two-year duration, an approach that could yield a better portrayal of the growth trajectory. Using this framework, the U.S. Q4 growth from 2020 to 2021 averaged 1.6 percent, while China's average stood at 5.2 percent, leading the U.S. by a wide margin. A key contributor was that the U.S. economy had just started to rebound in Q4 2020, and the 2020 quarterly reading, which was 2.3 percent lower than the previous year, compared with 6.4 percent growth of the Chinese economy in the same period.

Second, the quarter-on-quarter GDP growth rates of China and the U.S. in Q4 2021 are relatively close, with the growth in the U.S. primarily driven by restocking activities. The quarter-on-quarter GDP growth of China in the third and fourth quarters of 2021 were 0.7 percent and 1.6 percent, respectively, while those of the U.S. read 0.6 percent and 1.7 percent. Because of the different statistical calculation pattern and data presentation, Chinese authorities released a quarterly growth rate of GDP, while the U.S. published the quarter-on-quarter seasonally adjusted annual rate, known as QoQ SAAR, which makes U.S. data appear higher.Further number crunching shows that the higher U.S. growth in the Q4 2021 was in large part due to inventory restocking. If we take the 2012 constant price GDP as the baseline, U.S. SAAR GDP in Q4 2021 increased by $327.1 billion, of which the inventories alone amounted to $240.3 billion, contributing 73.5 percent to GDP growth.The inventory increment as a percentage of GDP in Q4 2021 was slightly above 0.9 percent, while the arithmetic average of inventory increment as a percentage of U.S. GDP throughout this century is 0.2 percent. If the quarterly inventory increment as a percentage of GDP for Q4 2021 is on par with the 0.2 percent level, then GDP growth for that quarter would be only 0.7 percent year-on-year, which translates into an annual rate of 2.9 percent, just slightly higher than the normal growth rate. And it would be significantly lower than China's QoQ growth rate.

The U.S. economy registered a growth rate of 5.7 percent in 2021, but it came at a high cost. Historically, annual U.S. GDP growth of 5.7 percent is rarely seen in half a century — it's a record high since 1985. It should be noted, however, that the U.S. economy outperformed in 2021 against a negative 3.4 percent growth rate in 2020. But the two-year average growth rate is only 1 percent, still below the long-term U.S. average economic growth rate.In particular, it should be noted that the U.S. has paid a hefty price to reverse the 2020 decline and achieve economic growth in 2021:First, the U.S. government has run massive deficits for two consecutive years. According to a joint report issued by the U.S. Treasury Department and the Office of Administration and Budget, the deficits for fiscal years 2020 and 2021 are as high as $3.13 trillion and $2.77 trillion, setting new records in U.S. history and resulting in deficit ratios of 15.2 percent and 12.4 percent, respectively.At the same time, due to the QE policy of the Federal Reserve, the broad money supply (M2) increased by $6.3 trillion in 2020-21, while the U.S. M2 supply was $15.4 trillion at the end of 2019, highlighting the substantial ballooning of the money supply over the past two years. The massive fiscal overspending and money printing led to severe inflation in 2021. According to the U.S. Bureau of Labor Statistics, the U.S. Consumer Price Index rose by 7.0 percent year-on-year in December, the highest monthly increase since 1982. By contrast, China's CPI rose only 0.9 percent in 2021, and thus managed to deliver high growth in tandem with low inflation.

Finally, we should not be overly optimistic of U.S. economic prospects in 2022. A few days ago, in the latest World Economic Outlook, the International Monetary Fund forecast that the U.S. economy will grow by 4 percent in 2022 and China by 4.8 percent. I think this is too optimistic for the U.S. and too pessimistic for China.As mentioned above, the U.S. achieved higher economic growth in 2021 on the back of a highly stimulative fiscal policy and excessively accommodative monetary policy. The U.S. will significantly cut its fiscal deficit in 2022 to tame inflation, and the Federal Reserve has indicated clearly its policy path of rate hikes and a balance sheet runoff.As the U.S. moderates the strength of its stimulus, coupled with a surge in the Omicron variant of the coronavirus since the end of 2021, consumer demand will be suppressed and supply chains disrupted, creating a drag on U.S. economic growth. The Conference Board, a leading U.S. economic analyst and research firm, projected U.S. GDP growth of 3.5 percent in January, which is significantly lower than the IMF's forecast.

In China, due to solid headway in the fight against the pandemic, the economy managed to get back on firmer ground quickly and has transitioned from fluctuations to greater stability. There is still headroom for adjustment of both fiscal and monetary policy, as the Chinese economy is expected to register a growth rate of over 5 percent this year.