We're pleased to report that Amphastar Pharmaceuticals shareholders have received a total shareholder return of 9.4% over one year. However, that falls short of the 17% TSR per annum it has made for shareholders, each year, over five years. The pessimistic view would be that be that the stock has its best days behind it, but on the other hand the price might simply be moderating while the business itself continues to execute. If you would like to research Amphastar Pharmaceuticals in more detail then you might want to take a look at whether insiders have been buying or selling shares in the company.