The bar chart compares the proportion of people using mobile phones across different age groups in a particular country between 1998 and 2000. Overall, although individuals aged 16-30 remained the dominant users of mobile phones, their usage rate gradually declined over the period. Similarly, a slight downward trend was observed among those aged 31-50. In contrast, mobile phones usage increased steadily among the youngest (<15) and oldest (50+) age groups, although a significant gap in usage remained between them and the middle-aged categories.