Cat Losing Hair In Patch?

Hello forum users,

     I have noticed that my cat appears to be losing hair on one side of his back in a patch that seems to be unusual. I do not want to take him to the vet because of associated costs. Do you guys/girls think this hair is unusual? I am going to enclose two pictures of the area, please let me know what you think - thanks.

Only a vet could answer this.. it could be allergies (food allergies?), or ringworms. 

Is he itchy? Scratching or biting at the area?

I have not seen him touching that area in particular at all, but he is usually hiding away so I am sure there is plenty of time for him to be attending to said area.