I kinda doubt that number took into account the taxes paid by hotels, restaurants, and stores which exist and make money only because of the sports team and stadium. Should the Vikings leave, many bars and restaurants will close, hotels will see lower profits/possible losses, and sporting goods stores which have a focus on NFL apparel will shutter. The NFL is the most popular/profitable professional sport in the US right now, losing the Vikings would be huge for MSP and the state of Minnesota.