What's really scary about those trendlines is that, unlike in years past, this year's line seems to show a steady, implacable decline downward. The downward trend has actually been going on since before the All-Star break, before the trade even happened. If you asked me to draw you a line to represent a team doing well for a while then simply running out of gas in the second half of the season, that's exactly what it would look like.
In '07-'08 and '08-'09, there was a high rate at the beginning of the year, then some turmoil in the middle, then a return back to the fiery pace towards the end (which is remarkable considering we were without KG at the end of the '09 season).
Last year, the team was plagued by inconsistency, and that shows in the graph. It wasn't until the playoffs that the team actually regained consistency, and it carried them to the Finals.
This season, the team was very consistent at the start of the year, and then has been on a consistent downward slide since a little bit past the midway point. That's really troubling.
That said, the line for this year does somewhat closely follow the line for '08-'09, so perhaps we can hope for a similar upturn at the end. That's still a troubling comparison, though, because in '08-'09 the team was without KG in the second half, so there was a clear explanation for that downward slide. This season, there is no one clear major factor to blame for that downward slide - nothing on the same level as losing one of the Big 4 for the entire second half.