I only went halfway down the page, but haven't yet stumbled upon the trend you're referring to?

The first few questions specifically asking about the topic show the opposite of what you claim.

The section I’m referring to is “Is there more crime in the U.S. than there was a year ago, or less?”.

Very interesting. The big swings in opinion don't seem timed to line up with national violent crime statistics. Maybe they correlate better with economic boom times and recessions. Or maybe perceptions are more weighted toward property crimes that have less reliable national statistics. Look at that dizzying drop in "more crime" responses between 1997 and 1998. The "more crime" responses stay low until 2002.

Or maybe there's just a lot of noise in the responses. "More crime" gained 10 points between 2004 and 2005.