They found that after a surprise departure, the probability that the company will subsequently have to restate earnings increases by nearly 20%.
译文：他们发现这类公司在外部董事忽然辞职后，需要重申收益的可能性增加了近两成。
请问这句话中的介词by的意思是？谢谢老师！
▲你的句中 by 表示增加或降低的幅度。又如：
The price has been increased by twenty-five pence. 价格上涨了25便士。
Tuition increased by 5% at universities this year. 今年大学学费上涨了5%。
Traffic has increased by 50% in ten years. 十年内车流量增加了五成。
The rate of inflation increased by 2%. 通货膨胀率增长了 2%。
▲句子结构剖析：在 the probability that the company will subsequently have to restate earnings increases by nearly 20% 中：
the probability：主语
that the company will subsequently have to restate earnings 为同位语从句，修饰the probability。
Increases：谓语
by nearly 20%：状语
▲注意：表示增加了多少，如果是increase用作动词，一般与介词 by连用；如果是increse用作名词，一般与介词of连用，比较：
数目增加了1 000。
正：The number increased by 1 000.
正：The number had an increase of 1 000.
这个城市的人口增加了百分之二十。
正：The population of the city has increased by 20 per cent.
正：The population of the city shows an increase of 20 per cent.
若表示“增加到…”，则用介词to：
His salary has increased to $3 000. 他的薪资已增加到3000USD。