【求助】一个翻译，12版OGP392

RayeRach

P392第一段最后一句。Duverger's research findings were that women voted somewhat less frequently than men(the difference narrowing the longer women had the vote).此句特别是括号里的什么意思？
还有对应的第95题E选项had possessed the right to vote for the shortest time怎么翻译呢？

谢谢大家！