Find the total number of EditorialReviews by platform and the average score given per platform/developer.

GB EditorialReview Scores By Developer

developers = {}
for er in EditorialReview.objects.all():
    print er
    for dtg in er.game.developers.all():
        if dtg.company.name in developers:
            _dict = developers[dtg.company.name]
            _dict['total_reviews'] += 1
            _dict['total_review_score'] += er.score
            _dict['avg_review_score'] = '%.1f' % (float(_dict['total_review_score']) / float(_dict['total_reviews']))
        else:
            developers.update({
                dtg.company.name:{
                    'total_reviews': 1,
                    'total_review_score':er.score,
                    'avg_review_score': er.score
                }
            })
print developers

GB EditorialReview Scores By Platform

platforms = {}
for er in EditorialReview.objects.all():
    print er
    for platform in er.platforms.all():
        if platform.name in platforms:
            platform_dict = platforms[platform.name]
            platform_dict['total_reviews'] += 1
            platform_dict['total_review_score'] += er.score
            platform_dict['avg_review_score'] = '%.1f' % (float(platform_dict['total_review_score']) / float(platform_dict['total_reviews']))
        else:
            platforms.update({
                platform.name:{
                    'total_reviews': 1,
                    'total_review_score':er.score,
                    'avg_review_score': er.score
                }
            })

print platforms

GB: EditorialReview Scores By Platform

platforms = {}
for er in EditorialReview.objects.all():
    print er
    for platform in er.platforms.all():
        if platform.name in platforms:
            platform_dict = platforms[platform.name]
            platform_dict['total_reviews'] += 1
            platform_dict['total_review_score'] += er.score
            platform_dict['avg_review_score'] = '%.1f' % (float(platform_dict['total_review_score']) / float(platform_dict['total_reviews']))
        else:
            platforms.update({
                platform.name:{
                    'total_reviews': 1,
                    'total_review_score':er.score,
                    'avg_review_score': er.score
                }
            })

print platforms

Can I use setdefault() to either speed this up?