Thousands of revelers lined the streets yesterday in Sunset Park to commemorate the Chinese New Year. Nearly 50,000 people found spots along 8th Avenue, with performances, firecrackers and a traditional parade marking the Year of the Dragon. Members of the Brooklyn Chinese-American Association say they were thrilled by the turnout, and that they have seen the neighborhood grow throughout the years. "We're seeing a lot of expansion within the community," says Association President Paul Mak, who started the parade 25 years ago. "We're seeing a lot of Asians that are moving in."