No, you haven't. It's all in your head. It goes up, then down, then up, then jiggs around a bit. The time frame between these events are something like 10-150 years. You need to look at 100 years or more at a time and take the average of it. Just looking at 30 years means nothing. You can't draw any conclusions. Science still doesn't know why it does this. Best guess has to do with activities on the sun, but it's still just guess work. England had a long time when they grew grapes for wine, in times when the science we have today tells us they shouldn't have been able to.
here's some info on it. I didn't read it carefully. Just the first page I found on it. http://www.ncpa.org/pub/st/st279/st279a.html