When analyzing data it is often important to use per capita values. These are values that take the factor you are looking at and divide it by the population. Per capita is latin for "by the head." If the values are very small which tends to be the case in a lot of instances then another measure is used: per 100,000 people.
Why use per capita? Often if you look at a trend in data it might look like it is rising, however it might simply be rising because the population is rising. To take away this effect you can divide each year's value by the population that year and you may find the trend is actually negative or muted by the population growth.