The Taiwan light source (TLS) is a 1.5 GeV third generation light source at the National Synchrotron Radiation Research Center (NSRRC) in Taiwan. It has been routinely operated since its opening in 1993. Several major machine upgrade projects have been undertaken and successfully completed in last 5 years, including implementing of digital bunch-by-bunch feedbacks, superconducting accelerating RF cavity, top-up mode injection, etc. The light source now moves forward to its era of mature operation. It delivers more than 5000 hours user time in 2007 with an up-time of more than 98% and a mean time between failures better than 80 hours. Here, we review its annual operational performance with detailed statistics and discuss the possible improvement directions of machine performance.