much more readable would be:

self.assertItemsEqual(data, [
    [u'Mon', 24123.0],
    [u'Tue', 16564.0], 
    [u'Wed', 25321.0], 
    [u'Thu', 22984.0],
    [u'Fri', 6426.0],
    [u'Sat', 0], 
    [u'Sun', 0],
])