"Relative importance" refers to the significance or value of something compared to other things or factors. It helps to understand the level of importance or priority assigned to different elements in relation to each other. Full definition
The declining casualty rates highlight the growing relative importance of the conflict's economic costs due to, for example, property damage, reduced business productivity, and defense spending. (academic.oup.com)
As we get closer to 2050 population growth becomes less of an issue and income growth and climate change grow in relative importance. (dotearth.blogs.nytimes.com)
Rather, absent context, we have no way to gauge relative importance and intensity of preference. (remakinglawfirms.com)