Slow Connection when using At&t Global Network Client

Whenever I connect to my company's VPN using AGNC, my connection speed drops significantly, even while I'm at work.

For example, I will kick off a 20 MB download from a website, internal to my company, while at work and the download speed will be 1.2 MB/s.

Then, I will launch AGNC and connect, while at work, and download the same 20 MB file, and the speed drops to 150 KB/s.

Is this dropoff normal? 

Here are some specs:

Windows 7 64-bit

AGNC version 8.8