11 months in, not pumping enough anymore

My daughter will be 11 months next week (YAY!) but I am barely pumping anything at work anymore, only about 4 ounces-down from almost 16. She is at grandma's from 6:45am-5:30pm and I don't know what to do. My freezer stash is pretty much gone. I've tried lactation cookies and pills but they don't seem like they are working. Do I start supplementing formula when I'm not with her? whole milk? Help me mamas!