nova/doc/api_samples/os-simple-tenant-usage/simple-tenant-usage-get.json

{
    "tenant_usages": [
        {
            "start": "2012-10-08T21:10:44.587336",
            "stop": "2012-10-08T22:10:44.587336",
            "tenant_id": "openstack",
            "total_hours": 1.0,
            "total_local_gb_usage": 0.0,
            "total_memory_mb_usage": 512.0,
            "total_vcpus_usage": 1.0
        }
    ]
}