Cost-sharing vs rental income

I am a relatively new homeowner and receive funds from a roommate that are about 60% of fair market rental value. I do not make a profit; the funds he gives are less than a third of the cost of the mortgage and HOA fees. All the bills are in my name. The use of the home by him is close to what is described here (he lives here as if it is his home, does not have a separate entrance, he has a private room and everything else in the home is shared, he buys his own groceries and cooks his own meals here, etc). However, he has signed a lease with me (required by my HOA for people other than homeowners to live in the building).

Does this difference mean the funds he gives me need to be reported as rental income to the IRS? Thanks.