Back when they were developed, coho and steelhead were the only goals based on some measure of habitat. The other three species were averages. A few comments.
When the Chinook goals were set WDF clearly noted that the goals were not designed to utilize the available habitat; much of which even at that time was un-used. They felt it was ludicrous to try and use all the available habitat. They also were proud of the fact they were having trouble hitting the wild goal in streams with large hatchery runs (the Green for example). This was before mass marking. The solution was to lower the goal, which the proudly pointed out that they hit.
Chum were based on the three highest years in the data base. Different goals for even and odd years because the presence of pinks depressed chum production. WDF did a stock recruit analysis on how well that goal was working, coupled with the boom in chum in the 80s and 90s. The results of running the Ricker Curve on the data was that goals were too low and needed to be raised. They weren't.
Pink, likewise, were averages. When I was still working the goal for the Puyallup was 19K, despite the returns of hundreds of thousands.
The Lake WA "goal" was intended to be only temporary. Actually, the 350K was to be applied only to the Cedar. That number was based on some recent year's data. Turns out they had mis-calculated the escapements and the interim goal should have been more in 500K range. Over time, the goal was lowered in that the whole watershed was managed for 350K. Production declines in recent years make Lake WA goal look a bit ridiculous.