Car urinating on sofas

Question
I have had my cat since she was 6 months old.  She is now turing six years and she was spayed right after I got her.  In the last year she has urinated on my sofa 5 or 6 times.  Her litter box is kept clean and I can't think of why she is doing this.  Any help would be appreciated.

Answer
Hello Shannon!

Question for you:  Think back to when these times happened. - Did anything change in her environment at about the same time this started happening?  Any new people, new furniture, or moved furniture?  Did you guys change residences?  Any new pets (like a bird, gerbil, cat, dog, etc.)?  Any food changes, or anything changes to his litterbox setup or placement?

Thanks!  I'll let you know with your answer.

Rosie