National Day (guó qìng jié ???) originally refers to the good or festive time. In ancient times of China, the most festive thing of one country must be the new emperor enthroned or the birthday of the king, which was regarded as the National Day. Since the People’s Republic of China was founded on October 1, 1949 with a ceremony at Tian’anmen Square, the Central People’s Government passed the Resolution on the National Day of the PRC (gu?n yú zh?ng huá rén mín gòng hé guó guó qìng jié de jué yì ???????????????) on December 2, 1949 and declared that October 1 is the National Day.
The celebration of National Day in China has changed for many times. During the period of 1950s, there were large-scale celebrations every year, at the same time with an inspection of troops. In September, 1960, the Central Government of China decided to reform the system of National Day’s celebration, with a guide line of economical. Then during the period of 1960 to 1970, there are National Day parades in Tian’anmen Square (ti?n ?n mén gu?ng ch?ng ?????), but no inspection of troops.
When the anniversary is a multiple of five (e.g. the 50th, 55th, or 60th), large scale official celebrations may be held, including an inspection of troops on Tian’anmen Square. More notable of these events included the inspection in 1984, the inspection in 1999 and the inspection in 2009.

Answer from Jennifer Zhu,

Professional Chinese Teacher from eChineseLearning

http://www.echineselearning.com/free-trial/index.html?ecl=ptEEEEEEye092803