That might be hard to come by.
Firstly, I suspect much traffic is provided by Service Providers, not Internet Service Providers (although many are one and the same company). So traffic for the former, might be confidential.
Even for traffic across the Internet, the Internet is private networks that cooperate for end-to-end delivery of traffic. Private peering points', data volume, let alone source and destination, might also be confidential. Even "public" peering points', data volume and source/destination might not be available (in full).
In the USA, and possibly other countries, the USA's NSA, and similar other country security organizations, might have the data you're after, but unlikely they will share it, in fact, they don't like to talk much about them even obtaining it.
Whatever data you might find, is likely to be only a subset or some guesstimate of what such stats might be.
