For example, it could be: $1 - $20 (denominations) small-size Federal Reserve Notes, Series of 1928 to Present Series, including ★ (star) notes. -or- $1 - $100 (denominations) small-size Federal Reserve Notes, Series of 1928 to Present Series, not including ★ (star) notes. Most people are not including an example of each district of each Series from Series of XXXX to Present... but one could. It is a serious challenge and expense to collect one of each of just one district. If you can that's just great! but there are keys within each district that present significant financial challenges if you are really trying to achieve all examples. Some people do collect that way, but this group is a bit more narrowly defined and trying to divide up amongst members the task at hand. Others may have a special reason that they prefer just one district if it appeals to a theme in their collection. You need to decide what appeals to you and what you like to collect.