History of Google Panda Updates

    Panda #21 on November 5th 2012
    Panda #20 on September 27th 2012
    Panda 3.9.2 on September 18th 2012
    Panda 3.9.1 on August 20th 2012
    Panda 3.9 on July 24th 2012
    Panda 3.8 on June 25th 2012
    Panda 3.7 on June 9th 2012
    Panda 3.6 on April 27th 2012
    Panda 3.5 on April 19th 2012
    Panda 3.4 on March 23rd 2012
    Panda 3.3 on about February 26th 2012
    Panda 3.2 on about January 15th 2012
    Panda 3.1 on November 18th
    Panda 2.5.3 on October 19/20th
    Panda 2.5.2 on October 13th
    Panda 2.5.1 on October 9th
    Panda 2.5 on September 28th
    Panda 2.4 in August
    Panda 2.3 on around July 22nd
    Panda 2.2 on June 18th
    Panda 2.1 on May 9th
    Panda 2.0 on April 11th
    Panda 1.0 on February 24th