One was purchased by my mother-in-law for her niece. It was kept at mi's home but rarely used. The date on it is 5 years ago.
My other one was the same situation- my mom's friend bought it for her granddaughter for when she came to visit. They used it like 4 times and it just sat in her garage. This was about 3 years ago.
I have another that a friend gave me that is 8 years old, so that one is definitely expired.
And the one from our 3 year old son somehow disappeared.
DH is home now with the new set up. :)