Up until January 1998, reprocessing of the data was conducted on an as needed basis, usually occurring every few weeks. In January 1998, the Project decided that reprocessing should be done less frequently, in order to provide the ocean color community with a more stable product. Also, the volume of data requiring reprocessing was making this approach impractical. As a result, the reprocessing procedure was formalized. Improvements to the algorithms were allowed to accumulate. No formal documentation from the period prior to January 1998 is available.