A new report from TrackMaven that analyzed 1,423 Twitter accounts and more than a million tweets was released today, showing what makes a successful tweet - which is a tweet that is re-posted by a lot of followers. The data suggests:

Time of day matters: Peak Twitter hours are during the workday, but retweets are actually higher during our off hours. On average, we retweet more on Sundays than we do on any other day of the week, and Twitter sees more retweets from 10-11 pm than it does for the rest of the day.

Hashtags and at-replies help: The use of hashtags and at-replies was also found to have a positive effect on the amount of times a tweet would be retweeted. Part of that is common sense--they give your tweets a much higher visibility--but the study also found that there are diminishing returns on tweets with more than six @ mentions.

Don't underestimate the period: When you incorporate @ mentions, don’t forget how valuable the period can be. Beginning your tweet with an @ makes it visible only to those who follow both you and the user you mention. But starting your tweet with a period, like .@ when it's necessary to start with another user’s handle makes sure that it will go out to all of your followers.

The report also notes the importance of using images to take advantage of Twitter's most recent redesign. Now that Twitter feeds display in-line image previews, tweets with images are almost 25% more likely to get retweeted.

Also, tweeting in all caps will net you .8 retweets on average per 1,000 followers, as opposed to tweets with only one-tenth of their text in caps, which averages out to .147 retweets per 1,000 followers.