This is the 470th most frequent Japanese word.
率
Rate; ratio.
率 is used here to describe the growth percentage, a measure of increase in a formal and quantitative sense.
この会社の成長率は前年比で10%増加しました。
The growth rate of this company increased by 10% compared to the previous year.
率 is part of a compound word here (効率), meaning efficiency, describing the effective usage or acquisition of resources.
市場シェアの高いメーカーは販売効率にも優れています。
Manufacturers with a high market share also excel in sales efficiency.
率 is utilized to indicate the proportion or percentage of successful applicants out of the total.