Inflation "Karma" on Habré

I noticed here recently that without changing the voting for my karma, its value fluctuates. At first she was moving towards zero (added). Naturally rejoiced, even though the fluctuations were small.

It was hoped to be sometime in the black, and learn to re-evaluate articles and topics in blogs.

But today I noticed a movement that is not desirable to me to a minus of infinity. sad so Do not tell me my friends, why is this happening?