Long story short, good estimates of overall mortality caused by sun exposure and sunburn do not exist. Some studies have even suggested that higher sun exposure reduces overall mortality. Unfortunately there is no answer to your question, but the following article outlines some of the risks and benefits to sun exposure:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5129901/
Long story short, good estimates of overall mortality caused by sun exposure and sunburn do not exist. Some studies have even suggested that higher sun exposure reduces overall mortality. Unfortunately there is no answer to your question, but the following article outlines some of the risks and benefits to sun exposure: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5129901/