Sorry for late response. Jik computer break and new (Vista) computer not work with old dialup internet service provider.
This is formula Jik use for max shop price:
1.5N * ( 1 + 0.00658Q )
where N is SUDE normal price and Q is QL.
This only work while product is fresh (SUDE supply not much over 100%). When product get stale (SUDE supply way over 100%), price come down fast. While product fresh, shop sell max quantity in every season, but when stale, seasonality have effect.
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Jik email IT team and they authorize post formula:
"it is not forbidden.
Is your formula correctly, you can post it in the forum.
The formula was written in the gamechat."