Thanks for pointing out the original price is still available to view! If I can't find out what the usual clearance price is, I'll just grab items that were originally most expensive.

I thought the usual clearance prices vary so much because the vendors chose the amount to discount--for example, ile-avalon's The Guardian Bundle is normally on clearance for around $11, if I remember correctly, so the end-of-year sale price is a great deal. But other items stay $3.50 or so all year long, so there's less incentive to snap them up now.