Here is an article about how many multivitamins contain either much less of certain nutrients or much more than is claimed on their labels.
Make sure you are getting what you pay for by choosing supplements that are independently tested for their nutrient content and potency. It can be dangerous to have too much of certain ingredients, and a waste of money and/or a lack of effectiveness to have too little. This is why all of the supplements that we endorse contain exactly what is on the label. We refuse to sell anything else in such an unregulated industry.