@Piggy has shown you the link to the core file to it all, although the referenced file (released on fridays) contains 120 days of TXs, and to go beyond you need to use files such as those created by @LoyceV.
Merit data is available in different formats and through different external tools (Im assuming you want to look beyond the 120 days of sMerit TXs that can be seen un the user profiles). The choice of which one depends on which one suits your needs best (i.e. consult somebodys merit history, get a general idea of how merit is being distributed and where, etc.).