With the recent release of three global datasets, you can now view youth, senior, and population density for more than 100 countries around the world. To create this map, I utilized demographic data from numerous distributors and ran a modified version of the Urban Observatory Data Loading Tools for each theme.
Click here* for the Youth Population Global Dataset.
Click here* for the Senior Population Global Dataset.
Click here* for the Population Density Global Dataset.
*The scales available are currently from 4,000,000 to 72,000; if you do not see the service, make sure you are searching the maps within the scale extent.