The number you specify for the bandwidth applies to both the egress and ingress traffic for the remote network connection. If you specify a bandwidth of 50 Mbps, Prisma Access provides you with a remote network connection with 50 Mbps of bandwidth on ingress and 50 Mbps on egress. Your bandwidth speeds can go up to 10% over the specified amount without traffic being dropped; for a 50 Mbps connection, the maximum bandwidth allocation is 55 Mbps on ingress and 55 Mbps on egress (50 Mbps plus 10% overage allocation).
https://docs.paloaltonetworks.com/prisma/prisma-access/prisma-access-panorama-admin/prisma-access-for-networks/how-to-calculate-network-bandwidth