all reports are broken by bad charms

All three reports

    http://staging.jujucharms.com/reports/charm-activity.json
    http://staging.jujucharms.com/reports/charm-contributors.json
    http://staging.jujucharms.com/reports/charm-count.json

fail for the same reason:

 2013-07-23 15:20:39 [1162] [ERROR] http://staging.jujucharms.com/reports/charm-activity.json
Traceback (most recent call last):
  ...
  File "/home/webops_deploy/charmworld/charmworld/views/reports.py", line 24, in json_charm_changes
    step=timedelta(7)).records()
  File "/home/webops_deploy/charmworld/charmworld/reports.py", line 247, in series_charm_changes
    for change in charm['changes']:
KeyError: 'changes'

The views are using charm_data instead of model. There is not guarantee that there is information to complete the graphs.