KKYY "Y95" was an Adult Contemporary station in San Diego, California from 1988 to 1990. 94.9 FM is currently Modern Rock KBZT.
CJXY "Y95.3" was a Classic Rock station from Hamilton, Ontario. In 2001, they swapped frequencies with CING moving up to 107.9 FM as "Y108" licensed to Burlington, ON.
KOY "Y95" was a Top-40 station in Phoenix, Arizona. 95.5 FM is currently Rhythmic Oldies "Eva 95.5"
I don't know what station this "Y95" shirt is from. Leave a comment if you do.
UPDATE: An anonymous poster in the comments below says the shirt is from KHYI Dallas/Ft. Worth, Texas. Thanks for the info!