On the eve of the Japanese and Australian leg of the Farewell Tour on January 31, 2001, Criss suddenly left the band once again, because he and the band could not come to agreement with his contract salary. Taking his place was previous Kiss drummer Singer who, in a move that was controversial among longtime fans, assumed Criss' Cat persona as the Farewell Tour continued.With the band supposedly set to retire by early 2001, a career-encompassing collection entitled simply The Box Set, consisting of 94 tracks on five CDs, was released in November of that year, while the summer saw perhaps the most outrageous item of Kiss merchandise yet – the Kiss Kasket. In introducing the Kiss Kasket, Simmons quipped, "I love livin', but this makes the alternative look pretty damn good."On December 4, 2001, Kiss was one of the honorees at the National Academy of Recording Arts and Sciences ("The Recording Academy") Heroes Award ceremony, at the NARAS New York Chapter. NARAS has 12 chapters throughout the United States, hence 12 ceremonies throughout the year, with the honorees each being honored by the chapter closest to their residence. By receiving this honor, which NARAS has renamed the "Recording Academy Honors", Kiss effectively received NARAS' second-highest career honor, right behind the Lifetime Achievement Grammy Award.Kiss was relatively quiet through the rest of the year, but 2002 started with some controversy as Simmons took part in a controversial interview on National Public Radio with host Terry Gross. In February 2002, Kiss (with Singer on drums and Frehley on lead guitar) performed during the closing ceremony of the 2002 Winter Olympics in Salt Lake City, Utah. This was Frehley's final performance as a member of Kiss.On March 6, 2002, Kiss performed a private concert at a resort in Trelawny, Jamaica. Frehley, who was no longer under contract, did not perform with the group. He was replaced by Thayer, who donned Frehley's Spaceman makeup and costume for his first live appearance with Kiss. That month, the band (with Thayer) taped an appearance on the American sitcom That '70s Show. The episode, "That '70s Kiss Show", aired in August 2002. Thayer again performed with the group in April 2002, when Kiss performed "Detroit Rock City" (with pre-recorded music and live vocals) for an appearance on Dick Clark's American Bandstand 50th Anniversary show, which aired on May 3.In February 2003, Kiss traveled to Australia and recorded Kiss Symphony: Alive IV with the Melbourne Symphony Orchestra at Etihad Stadium (then known as Telstra Dome) in Melbourne. Thayer once again replaced Frehley, while Criss returned to the group. This album was the first released on Sanctuary Records, which was later sold to Universal Music Group – owners of the rest of Kiss' catalog.Despite claims made prior to the Farewell Tour that it would be the group's last, Kiss toured with Aerosmith in 2003. Frehley announced that his departure from the band was permanent, stating that he believed the Farewell Tour would be Kiss' last, and that he did not want to open for Aerosmith. He was permanently replaced by Thayer, as Kiss moved into a post-reunion phase that saw the band easing into a new lineup, permanently featuring Thayer as "Spaceman" and Singer as "the Catman". On this tour, still featuring Criss, the group introduced the "Platinum" tickets package, with the most expensive packages costing $1,000. This package included a seat in the first five rows, a meet-and-greet with Kiss after their performance and a photograph with the band. The tour earned more than $64 million in 2003, which ranked seventh for the year.

Question: What year did Criss leave?
Answer: 2001