A complex study reveals something very simple.  We're happiest in the morning, before the rest of the day can bug us!
Cornell University looked at 500 million tweets sent by 2.4 million people from 84 countries over the past two years, and it all boiled down to the simple truth that we tend to be in the best mood in the morning.  Morning time is happiest, then moods go downhill for the rest of the day, until evening arrives and we're happy again.  The same thing happens on the weekends.  Why are the afternoons so bad?  Any clue?  Peak busy time evidently leads to big-time stress.  But it's also happy hour time.  That should help.
And we'd like to know, do you really reveal every bit of your worst mood on Twitter?  We think most people might hold back, so maybe the grouchy afternoons are really worse than we think.  Oh boy.
And that little bird makes Twitter look like such a happy place.  At least we know it is in the mornings, and after 7pm!  Happy Tweeting.