I hope prices have gone up since 2012?
It depends on what you mean by "prices." Yes, the market value has gone up slightly to about what you paid.
Charlton's BV has gone even higher but this doesn't make sense when almost all the Bird series took a serious hit in the book a few years ago (and very few notes have recovered). I have rarely seen sheets sell for about 75% of book value on eBay (so that's why I stated you got fair value). A few years ago they were selling for about 50% book.
I suppose Charlton could be getting their figures from i-collector (or other auctions) but I have never seen sheets of notes sell well at either shows (or on eBay). I used to attend a few of the GTA shows between 2006-2009 and saw the same dealers with the same rolls (sheets) of Multicoloured $1 & $2 and Birds $5 & $10. I spoke with a dealer and he told me, in confidence, that they sold similar to the "Lasting Impression" sets. They're just a tough sell.
BTW:
I stopped paying attention to i-collector because the end bids didn't make sense either (esp with the buyer's premium). I saw too many over-graded errors sold at 100-200% above book (because notes were VF to EF) but being passed off as UNC. The only logical explanation is US buyers have ran out of the their usual targets (1935 & 1937 notes) & were in bidding wars for these soiled/unimpressive error notes. (Errors are big in the US)
IMO: I really think it is hard to establish "what its worth" on many items these days as the older series are listed in US & only a little of the newer stock is listed in CDN or listed in true auction style on eBay these days. I don't think you can use i-collector as a valid yardstick to measure what any CDN note is worth right now.