Most times when people ask me how I'm doing, I reply with any of several variations of "good".  Even if it's the worst day of my life, I don't really want to take the time and burden someone else with all my problems.  Plus, these feelings are usually temporary.  If I just sat in 2 hours of traffic, I'm usually as mad as I can possibly get.  But it goes away.  If I voiced my feelings on it, some people would probably recommend me for psychiatric evaluation.  And it's also difficult to quantify how I am at any given point in time.  At 3:45pm, I might be doing great because I just found a quarter in the parking lot.  But at 3:47pm, I might be doing awful because I accidentally inhaled and swallowed a bug.  So if an answer is even given, it's usually based on the most recent experience.  Taking the average of my feelings over a certain period of time doesn't really work either.  I couldn't realistically say, "I'm doing terrible because I just stubbed my toe on that rock over there.  But last month I bought a new digital camera, so I'm doing pretty well on average."  I think the real answer should depend on how you are at the exact moment the question is posed, regardless of what happened in the past hour, day, or week.  So if you're alive, well, breathing, and remotely healthy, the answer should be any of several variations of "good". 

It's funny when people say how they really feel.  I treat the question like a greeting.  It's normally preceded by a "hey" or a "hello".  Some people treat it like an invitation to tell their life story.  So the conversation goes something like this: 
Them:  "Hey, how's it going?" 
Me:  "Not bad.  How are you?" 
Them:  "Terrible.  Today is the worst day of my life.  I just sat through the longest day of meetings in my life.  I hate my job.  I don't even know why I go.  Then I sat in 2 hours of traffic on Route 80, where people were cutting me off and beeping at me.  Sometimes I just want to carry a gun with me.  Ya know what I mean?  When I finally got home, my dog and cat got in a terrible fight and killed each other.  I got in a car accident on my way to meet you.  And then I accidentally sat on my last Butterscotch Krimpet.  I wish I was never born." 
This is frighteningly similar to a conversation I had last night.  I don't mean to seem like a uncaring jerk, but I guess I just didn't expect to get a real answer to my question.  The question was more of a greeting than an actual question.  I guess I should be careful what I ask. #psychology