I think you wouldn't be far off the 6-8% range.... Most distributors get $10-$20 / ton on commodities.

$450 @ 6% = $27

$400 @ 6% = $24

$350 @ 6% = $21

$300 @ 3% = $9

My guess.... and this is a Wild A$$ Guess.... is that the scale of discount will fluctuate 3% - 6% range....

$27 / ton at $450 potash is a very good discount IMO!