It took 32 years for mentions of 1880 to peak and then fall by half, a mark considered crucial by the researchers, compared with a 10-year span for references to 1975.

结果显示，“1880”这个年份出现在书中的频率在1832年达到顶峰然后跌落至一半水平，这在研究人员看来是个重要的临界点，而与之参考的“1975”年只用了十年就达到了最高点临界水平。

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This was the first fall in a decade and dashed hopes that the life span of the average Russian would beat the Gorbachev-era peak and exceed 70 years for the first time ever.

WSJ: A Lost Opportunity to Save Russia