Havard and Yale work on the premise of you pay about 10% of your family income, and the rest is funded via FA and campus work. So if your family income is about 100000, you pay about 10K. The other Yvies are not quite as generous and 15 to 20% is more of the norm. The rates are variable as there are other factors involved, such as other kids attending schools and capital assets. Some other Ivies have a so called matching program, that can enhance your FA. That is typically set aside for Blue Chippers. They will also help you more if you are an academic booster (30+ on the ACT or 2000+ on the SAT, along with a 95+ % average)
Most people who have kids attending Ivies know of the HYP vs the rest syndrome.