For both my bank accounts I can only access 18 months of history.
To access older account history, you have to pay a certain amount of money for each old statement. Why do banks do that? Shouldn't this practice go away as we get bigger hard disks and cheaper storage?
The Achilles Heel of nearly all data storage solutions is backup. Nobody wants to keep data that is infrequently accessed on-line if they don't have to because online data costs more than offline data. Unfortunately, once the data is no longer online, it becomes much harder to get at, often involving manual processes. Whether the data is truly not available online anymore or not, this is the origin of the fee for accessing older data.
I know that we remove older data for our students about 13 months after they leave the University. And, yes, we too charge a fee to recover the data once it has been removed to offline storage.