A Case Study of the Weathering of Treated Lumber

How quickly does treated lumber weather?
Here is a photo I took of a picnic table near our office on June 15, 2016

Figure 1 Treated lumber picnic table few days after it was set up.
Here is the same table from a similar angle approximately nine months later.

Figure 2 Treated lumber picnic table nine months after it was set up.
The lumber has begun to lose its yellow-brown color and is beginning to show a grey brown color. Some boards have appear to have faded more than others, but these were already differing in color from the start.